Chapter 9

Thinking This through Logically: Critical Reasoning

IN THIS CHAPTER

check Getting the lowdown on the makeup of GMAT critical reasoning questions

check Deducing the nitty-gritty of informal logic

check Distinguishing among the different question types

check Practicing your approach for each type of critical reasoning question

You’re taking the GMAT to go to business school, not to get a PhD in philosophy, so you’re probably wondering why you need to be tested in logic and critical reasoning. Don’t worry — answering the critical reasoning questions on the GMAT doesn’t require any knowledge of formal logic. You won’t be constructing syllogisms or using fancy Latin words, like ad hominem, for logical fallacies. The GMAT verbal section contains questions that test you on informal logic, which is a lot like the kind of reasoning you use to decide between a chocolate frosted doughnut and a bran muffin when the office pastry cart passes by. We fill you in on this logic (for the GMAT, not the pastry cart) in this chapter. The people who run the admissions offices at business schools want to make sure their future students can think through situations clearly and carefully. That’s where the critical reasoning question comes in.

About a third of the questions in the GMAT verbal section are critical reasoning questions. This question type tests your ability to analyze an argument. The good news is that you analyze arguments all the time, even though you may not know you’re doing so. When you see a commercial advertising a new product that claims it’ll make your life better, you probably question that claim. If a weight-loss drug helped someone lose 50 pounds, you ask, “Is that a typical result?” If four out of five dentists recommend a chewing gum, you say, “Did they ask only five dentists?” When a mutual fund boasts of its performance, you ask, “Is that better than the market average?” You’ll use this same kind of thinking to ace the critical reasoning questions on the GMAT.

Focusing on “Critical” Concepts: An Overview

Critical reasoning questions consist of an argument, a question, and five answer choices. You’ll encounter short passages from a variety of sources, such as speeches, advertisements, newspapers, and scholarly articles. You may see an argument like this: “The local sales tax must be raised to fund city services. Admittedly, this increased sales tax will impose a greater hardship on the poorest citizens. But if the sales tax is not increased, all city services for the poor will have to be cut.” The paragraph reflects the type of arguments you encounter in the news every day.

In the following sections, we clue you in on what to expect when you approach a critical reasoning question on the GMAT — from the length and format of the argument, to the type of questions you’ll be asked, to how to figure out the correct answer.

Understanding the structure of the questions

Each critical reasoning question has essentially the same structure. The question usually begins with a two- to five-sentence paragraph that contains the argument. The question contains all the information you need to answer the question. Don’t rely on any outside information! Even if you happen to be an expert in the area a question covers, don’t rely on your expertise to answer the question.

The short argument paragraph is followed by a question. The questions usually fall conveniently into one of a few types. The question may ask that you weaken or strengthen an argument, draw a conclusion, analyze the structure of an argument, or identify an unstated assumption the author makes. We examine each of these question types in the section “Getting from Point A to Point B: Types of reasoning,” later in this chapter.

Each question has five possible answer choices, which are often long, sometimes even longer than the argument or question. For this reason, you’ll spend most of your time for each question examining the answer choices.

As with most GMAT questions, you can quickly eliminate one or two of the answers that are obviously wrong. The remaining answers will be more difficult to eliminate, so spend your time analyzing these better answer choices.

Figuring out how to answer the questions

To break down a critical reasoning question, follow these three steps:

Read the question.
Read the argument paragraph, focusing on the specific information you need to know to answer the question.
As you read the argument, look for inconsistencies and/or assumptions in the logic.

The best way to tackle a critical reasoning question is to read the question first to determine its type. The later section “Thinking Inside the Box: Question Types” shows you how to distinguish critical reasoning question types. When you first read the question, don’t read all the answer choices; doing so takes way too much time and clutters your thinking. You need to concentrate on only the information you need to find to answer the question.

After you figure out what kind of question you’re dealing with, you can read the paragraph very carefully. Be sure to locate the conclusion of the argument. The conclusion may come at the beginning, middle, or end of the paragraph. When you’ve identified the conclusion, you can better understand the rest of the paragraph. As you read the paragraph, look for inconsistencies or gaps in the argument that may help you answer the question. Isolating the argument’s premises, assumptions, and conclusion helps you determine the method of reasoning.

The argument paragraph usually isn’t too complicated, and therefore you may be tempted to read it too quickly. Force yourself to read slowly and carefully so you don’t skim over the word or words that provide the keys to the argument. If you read thoroughly enough, you’ll be able to eliminate some — or even most — of the answer choices. When you’re down to two possible answers, you can then easily refer back to the text to make sure you choose the correct answer.

Making a Case: Essentials of Informal Logic

You can score well on the GMAT critical reasoning questions without knowing the elements of informal logic, but if you understand a few terms and concepts, you can score even higher. You really just need to know the two basic components of a logical argument and a few methods of coming up with a conclusion, which we outline in the following sections.

Fighting fair: The elements of an argument

A logical argument consists of premises and a conclusion, and when you’re analyzing arguments, identifying what parts are premises and what makes up the conclusion can help. The premises give the supporting evidence that you can draw a conclusion from. You can usually find the conclusion in the argument because it’s the statement that you can preface with therefore. The conclusion is often but not always the last sentence of the argument. For example, take a look at this simple argument:

All runners are fast. John is a runner. Therefore, John is fast.

The premises in the argument are “All runners are fast” and “John is a runner.” They provide the supporting evidence for the conclusion that John is fast, which is the sentence that begins with therefore. Not all conclusions in the GMAT critical reasoning arguments will begin with therefore or other words like it (such as thus and so), but you can try adding therefore to any statement you believe is the conclusion to see whether the argument makes sense. We give you plenty of sample arguments in this chapter so you can use them to practice identifying premises and conclusions.

Getting from Point A to Point B: Types of reasoning

Each logical argument has premises and a conclusion, but not every argument comes to a conclusion in the same way. For the purposes of the GMAT, you should be familiar with two basic types of logical reasoning: deductive and inductive (which we explain further in the next sections). You use both types of reasoning all the time, but now you can apply definitions to your logical genius.

Elementary, my dear Watson: Deductive reasoning

In deductive reasoning, you come up with a specific conclusion from more general premises. The great thing about deductive reasoning is that if the premises are true, the conclusion must be true! The following is an example of a deductive reasoning argument:

All horses have hooves. (General premise)
Bella is a horse. (More specific premise)
Therefore, Bella has hooves. (Very specific conclusion)

SURE SOUNDS GREEK TO ME: ORIGINS OF LOGICAL THOUGHT

Legend has it that a Greek philosopher named Parmenides in the 5th century BC had plenty of time on his hands while living in a Greek colony off the west coast of Italy. So he whiled away the hours contemplating logical thought and became one of the first Westerners to record his findings. He penned a philosophical poem in which an unnamed goddess instructs him in the ways of determining truth about the universe. His poem explored the contrast between truth and appearance and portrayed truth to be firm and steadfast, whereas appearance (the way mortal men usually think) was unstable and wavering. Parmenides’s work influenced other great Greek thinkers, like Plato, Aristotle, and Plotinus.

Unfortunately, you won’t have a goddess to guide you through the critical reasoning questions of the GMAT, but you can rely on Aristotle’s method of developing syllogisms to examine GMAT arguments. He’s the one who came up with this famous syllogism: “All humans are mortal; Socrates is human; therefore, Socrates is mortal.”

If the premise that all horses have hooves is true, and if Bella is, in fact, a horse, then it must be true that Bella has hooves. The same holds true for all examples of deductive reasoning. Here’s another example:

All who take the GMAT must complete an analytical essay. (General premise)
You’re taking the GMAT. (More specific premise)
Therefore, you have to complete an analytical essay. (Very specific conclusion)

This example shows the relationship between the truth of the premises and that of the conclusion. The first premise is categorically true: The GMAT requires you to write an essay. The second premise, however, may not be true. Certainly, you’re thinking of taking the GMAT or you wouldn’t be reading this book, but you may still decide not to take the test. This possibility doesn’t affect the logic of the argument. Remember, in deductive reasoning, the conclusion must be true if the premises are true. If you take the test, you have to write an essay, so this argument is valid.

When you analyze deductive reasoning arguments for the GMAT, the only way you can prove that a conclusion is true is by showing that all premises are true. The only way to prove that a deductive reasoning conclusion is false is to show that at least one of the premises is false.

Perhaps I’m just generalizing: Inductive reasoning

In deductive reasoning, you draw a specific conclusion from general premises. With inductive reasoning, you do just the opposite; you develop a general conclusion from specific premises. Inductive reasoning differs from deductive reasoning in that the conclusion in an inductive reasoning argument could be false even if all the premises are true. With inductive reasoning, the conclusion is essentially your best guess. That’s because an inductive reasoning argument relies on less complete information than deductive reasoning does. Consider this example of an inductive argument:

Bella is a horse and has hooves. (Specific premise)
Smoky is a horse and has hooves. (Specific premise)
Nutmeg is a horse and has hooves. (Specific premise)
Shadow is a horse and has hooves. (Specific premise)
Therefore, it is likely that all horses have hooves. (General conclusion)

Because inductive reasoning derives general conclusions from specific examples, you can’t come up with a statement that “must be true.” The best you can say, even if all the premises are true, is that the conclusion can be or is likely to be true.

Inductive reasoning arguments come in all sorts of flavors, but the folks who create the GMAT tend to favor three types: analogy, cause and effect, and statistical. To excel on the GMAT, you want to get very familiar with these three methods of inductive reasoning:

Analogy arguments: An analogy argument tries to show that two or more concepts are similar so that what holds true for one is true for the other. The strength of the argument depends on the degree of similarity between the persons, objects, or ideas being compared. For example, in drawing a conclusion about Beth’s likes, you may compare her to Alex: “Alex is a student, and he likes rap music. Beth is also a student, so she probably likes rap music, too.” Your argument would be stronger if you could show that Alex and Beth have other similar interests that apply to rap music, like hip-hop dancing or wearing bling. If, on the other hand, you show that Alex likes to go to dance clubs while Beth prefers practicing her violin at home, your original conclusion may be less likely.
Cause-and-effect arguments: A cause-and-effect argument concludes that one event is the result of another. These types of arguments are strongest when the premises prove that the alleged cause of an event is the most likely one and that no other probable causes exist. For example, after years of football watching, you may conclude the following: “Every time I wear my lucky shirt, my favorite team wins; therefore, wearing my lucky shirt causes the team to win.” The above example is weak because it doesn’t take into consideration other, more-probable reasons (like the team’s talent) for the wins.
Statistical arguments: Arguments based on statistical evidence rely on numbers to reach a conclusion. These types of arguments claim that what’s true for the statistical majority is also true for the individual. But because these are inductive-reasoning arguments, you can’t prove that the conclusions are absolutely true. When you analyze statistical arguments on the GMAT, focus on how well the given statistics apply to the circumstances of the conclusion. For example, if you wanted people to buy clothing through your website, you might make this argument: “In a recent study of the preferences of consumers, 80 percent of shoppers surveyed spent more than six hours a day on the Internet; therefore, you’ll probably prefer to buy clothes online.” You’d support your conclusion if you could show that a positive correlation occurs between the amount of time people spend on the Internet and a preference for buying clothing online. If you can’t demonstrate that correlation, the statistics regarding time spent on the Internet have little to do with predicting one’s preference for online shopping.

To do well on the critical reasoning questions, you need to recognize premises and conclusions in arguments, determine whether the argument applies deductive or inductive reasoning (most will be inductive), and, if the argument is inductive, figure out the method the author uses to reach the conclusion. As you can induce, knowing a little about logical reasoning is essential to scoring well on the GMAT!

Thinking Inside the Box: Question Types

When you were growing up, you probably experienced clichés. You had your jocks, your stoners, the smart kids (that was you!), and various other categories. Labels were important because they gave you clues on how to deal with someone who was a member of a particular group. You knew better than to pick a fight with a jock, and it was a good bet that you could get a match from a stoner. Well, we categorize GMAT questions for the same reason. After you figure out a critical reasoning question’s type, you know just how to deal with it. Most of the critical reasoning questions you’ll encounter on the GMAT fit into one of the following five categories:

Strengthening or weakening arguments: The argument presents premises and a conclusion and asks you to evaluate the answer choices to determine which one would best strengthen or weaken the author’s conclusion.
Drawing conclusions from premises: The argument paragraph consists of a bunch of premises but doesn’t provide a conclusion. Your job is to choose the best conclusion for the argument.
Seeking assumptions: This more-subtle type of question requires you to discover an essential premise of the argument that the author doesn’t state directly.
Making inferences: For these less-common question types, you have to surmise information that isn’t directly stated, usually about one of the premises rather than the conclusion.
Finding the method of reasoning: In these questions, you’ll be asked to find an argument in the answer choices that uses the same method of reasoning as the original given argument.

Because each question type has a best way to handle it, recognizing what type of question you’re dealing with before you try to answer it is important. That’s why you read the question before you tackle the argument. You’ll immediately know what you need to look for when you read the argument from the wording of the question.

Stalking Your Prey: How to Approach Each Question Type

Knowing the types of questions you’ll face is valuable only if you know the specialized strategies for dealing with each one. The following sections give you the tips you need to make approaching each of the question types second nature. You get some practice questions, too, so you’ll know just what to expect when you take the actual GMAT.

Strengthening or weakening arguments

Critical reasoning questions that ask you how to best support or damage an argument are some of the easiest to answer, which is a good thing because they appear the most frequently. You probably analyze ideas every day and think of evidence to attack or defend those ideas. Because you already have the skill to evaluate arguments, it doesn’t take much work for you to modify that skill to fit this specific GMAT question format. This question category has two subtypes: One asks you to strengthen an argument, and the other asks you to weaken it. You’ll recognize these questions because they include words that mean to strengthen or weaken (like support, bolster, or impair), and they almost always contain an “if true” qualifier.

Here are a couple samples of the ways the questions could be worded:

Which of the following statements, if true, would most seriously weaken the conclusion reached by the business owners?
Which of the following, if true, provides the most support for the conclusion?

Nearly all these questions contain the words if true, but not all questions that have if true in them are strengthening- or weakening-the-argument types. To make sure an “if true” question is really a strengthening or weakening question, look for the identifying language that asks you to either strengthen or weaken the argument.

Here are three simple steps to follow when approaching strengthening- or weakening-the-argument questions:

Read the question carefully so you know exactly what you’ll be strengthening or weakening.

In most cases, you’ll be asked to strengthen or weaken the conclusion of the main argument. But in less-frequent cases, you may be asked to support or impair a different conclusion, like the view of the author’s opponent.
Examine the argument to find the premises and conclusion and to determine what method of reasoning the author uses to reach the conclusion.

Usually the author uses inductive reasoning, so you’ll need to figure out whether the argument relies on analogy, statistics, or cause and effect to arrive at the conclusion. In the following sections, we tell you what to look for in each type of reasoning.
Evaluate the answer choices to determine which choice best fits with the author’s conclusion and method of reasoning.

Assume all the answer choices are true and then determine which one best either supports or undermines the specific conclusion addressed in the question.

Always assume that all the answers to strengthening- or weakening-the-argument questions are true. Almost all these questions include the words if true in them to remind you that you’re supposed to assume that each answer choice presents a true statement. Don’t fall into the trap of trying to evaluate whether answer choices are true or false! Your only job is to determine whether the choices help or hurt the argument. This means that a statement like “humans do not breathe air” could be a correct answer choice even though you know it’s not true. Perhaps you’re supposed to weaken the conclusion that a company must pump air into an underwater habitat for humans. If humans don’t breathe air, pumping in air may not be necessary. Make sure you don’t dismiss any answer choices simply because you know they aren’t usually true.

Analyzing analogy arguments

Analogy arguments rely on the similarity of the two persons, things, or ideas being compared. Therefore, if the author uses an analogy to reach a conclusion, answer choices that show similarities between the compared elements will support the conclusion, and choices that emphasize the differences between the elements will weaken the conclusion. Take a look at this example of an analogy argument.

Example Hundo is a Japanese car company, and Hundos run for many miles on a gallon of gas. Toyo is also a Japanese car company; therefore, Toyos should get good gas mileage, too.

The author’s conclusion would be best supported by which of the following?

(A) All Japanese car manufacturers use the same types of engines in their cars.

(B) British cars run for as many miles on a tank of gas as Hundos do.

(D) Toyo has been manufacturing cars for more than 20 years.

(E) All Japanese cars have excellent service records.

Recognizing the premises and conclusion in this argument is simple. The author states directly that Hundo cars are Japanese and get good gas mileage and that Toyo cars are Japanese; therefore, Toyos also get good gas mileage. Your job is to find the answer that perpetuates the similarity between Hundos and Toyos.

Tip You can generally eliminate answer choices that introduce irrelevant information, such as Choices (B), (D), and (E). The author compares Japanese cars, so what British cars do has nothing to do with the argument. The length of time that Toyo has been in business tells you nothing about how similar its cars are to Hundo’s. And the question is talking about gas mileage, not service records, so don’t spend too much time considering Choice (E).

Choice (C) tells you the focus of Toyo producers, but it doesn’t give you any information about how that compares to Hundo, so the best answer is Choice (A). If all Japanese manufacturers supply their cars with the same engines and Hundo and Toyo are both Japanese manufacturers, it’s more likely that Toyos will achieve a gas mileage similar to that experienced by Hundos.

Considering cause-and-effect arguments

Questions that ask you to evaluate arguments often apply cause-and-effect reasoning. If the argument uses cause and effect to make its point, focus on the causes. Almost always, the correct answer to a question that asks you to strengthen the conclusion is an answer choice that shows the cause mentioned is the most likely source of the effect. The best answer for a question for which you have to weaken the argument points to another probable cause of the effect. Here’s how you’d apply this reasoning to a sample question.

Example Average hours of television viewing per American have rapidly increased for more than three decades. To fight the rise in obesity, Americans must limit their hours of television viewing.

Which of the following, if true, would most weaken the author’s conclusion?

(A) A person burns more calories while watching television than while sleeping.

(B) Over the last 30 years, the number of fast-food restaurants in America has increased.

(D) Television viewing in Japan has also increased over the past three decades.

(E) Studies show that the number of television commercials that promote junk food has risen over the past ten years.

To tackle this question, first identify the conclusion you’re supposed to weaken and the premises the author states or implies to reach that conclusion. The conclusion is pretty easy to spot. The last thought of the argument is that Americans must limit their hours of television viewing to curb the rise in obesity. The author makes this judgment using the following evidence:

The author directly states that the number of television viewing hours has increased over the last 30 years.
According to the author, the number of obese Americans has also increased.
The author implies that television viewing causes obesity.

To weaken the argument that Americans have to reduce their television watching, you have to find the answer choice that shows that there’s another cause for the rise in obesity.

You may have been tempted to select Choice (A) because it shows that television watching may be less fat-producing than another activity, sleeping. But it doesn’t give you another reason for the rise in obesity. Choice (A) could be correct only if it showed that Americans were sleeping more than they were 30 years ago. It doesn’t, so move on.

On the other hand, stating that during the same time period, the number of fast-food restaurants also increased introduces another possible cause of obesity and weakens the conclusion that Americans have to stop watching so much TV to get slimmer. Maybe it’s the popularity of fast food that’s the culprit! Choice (B) is a better answer than Choice (A), but read through all the possibilities before you commit. Choice (C) is wrong because there’s nothing in the argument that suggests that the type of television Americans watch affects their obesity; nor does Choice (C) show that viewing patterns have changed over the last three decades. Choice (D) is also out because it doesn’t correlate what’s happening in Japan with what’s happening in America. You don’t know whether Japanese citizens weigh more now than they did 30 years ago, so the information in Choice (D) is useless.

If the question had asked you to strengthen the conclusion, Choice (E) would be a good option. It shows a reason that increased television watching could cause obesity. But the question asks you to weaken the conclusion, so Choice (B) is the best answer. It’s the only one that shows that another cause could be to blame for the rise in obesity.

Taking a stab at statistical arguments

If you see statistics used to promote an argument, you’re looking for an answer that shows whether the statistics actually relate to the topic of the conclusion. If they do, you’ll strengthen the conclusion. On the other hand, an answer choice that shows the statistics are unrelated to the conclusion significantly weakens that conclusion. The following is an example of a statistical argument critical reasoning question you could find on the GMAT.

Example In a survey of 100 pet owners, 80 percent said that they would buy a more expensive pet food if it contained vitamin supplements. Consequently, CatCo’s new premium cat food should be a top-seller.

Which of the following best demonstrates a weakness in the author’s conclusion?

(A) Some brands of cat food contain more vitamin supplements than CatCo’s does.

(B) CatCo sells more cat food than any of its competitors.

(D) Ninety-five of those pet owners surveyed did not own cats.

(E) Many veterinarians have stated that vitamin supplements in cat food do not greatly increase health benefits.

Because the argument hinges on statistics, eliminate answers that don’t directly address the statistical evidence. Those surveyed stated that they’d pay more for pet food with vitamin supplements, but they didn’t provide information on whether the amount of vitamin supplements was important. So even though Choice (A) may entice you, it isn’t the best answer because it doesn’t address the statistics used in the argument. Choice (B) doesn’t regard the survey results, either, and it supports the conclusion rather than weakens it. The argument has nothing at all to do with veterinarians, so Choice (E) can’t be right. Only Choices (C) and (D) deal with the survey the author uses to reach the conclusion that CatCo’s premium cat food will be a big seller.

Tip You can eliminate answer choices that show an exception to the statistical evidence. Exceptions don’t significantly weaken a statistical argument.

Therefore, Choice (C) is wrong and Choice (D) is the best answer because it demonstrates a weakness in the statistics the author uses to support the conclusion. The preferences of dog or bird owners isn’t a good indicator of the habits of cat owners.

Dabbling in deductive-reasoning arguments

Rarely will you see a strengthen- or weaken-the-argument question that uses deductive reasoning to reach a conclusion. It’s just too hard to come up with challenging answer choices for weakening deductive arguments, because the only way to weaken them is to question the accuracy of the evidence, and correct answers are pretty easy to spot. The only way to strengthen a deductive argument is to reinforce the validity of the premises, which seems sort of silly. Even though GMAT creators don’t want to make things too easy for you, one or two deductive arguments may crop up. To weaken an argument with a conclusion that must be true, look for an answer choice that shows that one of the premises is untrue. For example, you may see a question with the following argument:

All horses have tails. Nutmeg is a horse. Therefore, Nutmeg must have a tail.

The only way to weaken this argument is to question one of the two premises. Answer choices like “Scientists have recently developed a breed of horses that has no tail” or “Although Nutmeg looks like a horse, she’s really a donkey” would weaken the conclusion.

Delving into drawing conclusions

Another common critical reasoning question type tests your ability to draw logical conclusions (or hypotheses). The GMAT gives you a series of premises (the evidence), and you choose an answer that best concludes the information. Questions that ask you to draw conclusions from premises may be worded like this:

Which of the following conclusions is best supported by the preceding information?
Assuming the preceding statements are true, which of the following must also be true?
The experimental results support which of the following hypotheses?

As you read through the premises, think of a logical conclusion of your own. Then look through the answer choices to see whether one listed comes close to what you’ve thought up.

The key to correctly answering drawing-conclusions questions is to look for an answer choice that addresses all the information contained in the premises. Eliminate any choices that are off topic or incomplete. A conclusion that addresses only part of the information may be plausible, but it probably isn’t the best answer. For example, consider the following premises:

Five hundred healthy adults were allowed to sleep no more than five hours a night for one month. Half of the group members were allowed 90-minute naps in the afternoon each day; the remaining subjects were allowed no naps. Throughout the month, the subjects of the experiment were tested to determine the impact of sleep deprivation on their performance of standard tasks. By the end of the month, the group that was not allowed to nap suffered significant declines in their performance, while the napping group suffered more moderate declines.

The best conclusion for these premises would have to address all the following:

The nightly sleep deprivation of healthy adults
The allowance for naps for half of the study group
The smaller decline in performance of standard tasks for the group who took naps

Any conclusion that fails to address all three points isn’t the best conclusion. For example, the statement “Sleep deprivation causes accumulating declines in performance among healthy adults” wouldn’t be the best conclusion because it fails to address the effect of naps. A better conclusion would be “Napping helps reduce the declines in performance caused by nightly sleep deprivation among healthy adults.”

You’ll often see more than one plausible conclusion among the answer choices. Your task is to identify the best choice. Don’t fall for the trap of choosing an answer that just restates one of the premises. Answer choices that restate a premise may entice you because they echo part of the information in the argument, but the best choice must contain an element of each of the pieces of information presented in the question.

The process is pretty simple, really. Try this sample question to see for yourself.

Example Over the last eight years, the Federal Reserve Bank has raised the prime interest rate by a quarter-point more than ten times. The Bank raises rates when its Board of Governors fears inflation and lowers rates when the economy is slowing down.

Which of the following is the most logical conclusion for the preceding paragraph?

(A) The Federal Reserve should be replaced with regional banks that can respond more quickly to changing economic conditions.

(B) The Federal Reserve has raised the prime rate in recent years to try to control inflation.

(D) The monetary policy of the United States is no longer controlled by the Federal Reserve.

(E) The Federal Reserve has consistently raised the prime rate over the last several years.

You know from the language that this is a drawing-conclusions question, so you don’t have to look for a conclusion in the argument. Just read through the premises and formulate a quick conclusion, something like “Because the Federal Reserve has raised interest rates many times over the last eight years, it must fear inflation.”

Eliminate answer choices that aren’t relevant or that contain information not presented by the premises. The argument says nothing about regional banks or the termination of the Federal Reserve’s control over U.S. monetary policy, so you can disregard Choices (A) and (D). Then get rid of any choices that don’t take all premises into consideration. Choice (E) just reiterates the first premise, so it’s wrong. You’re left with Choices (B) and (C), but Choice (C) contradicts the information in the premises. The problem says the Federal Reserve responds to the economy, not the other way around, so it’d be wrong to say the Federal Reserve causes a recession. Choice (B) is clearly the best answer. It takes into consideration the information that the Federal Reserve has raised rates and that raising rates is its response to inflation.

Warning Be careful to avoid relying on outside knowledge or opinions when answering drawing-conclusions questions. You may have studied the Federal Reserve Bank and have opinions about monetary policy. Choices (A), (C), and (D) reflect some possible opinions about the Federal Reserve. Don’t get trapped into choosing an answer because it supports your opinion.

Spotting those sneaky assumptions

Some GMAT critical reasoning questions ask you to identify a premise that isn’t there. For these types of questions, the author directly states a series of premises and provides a clear conclusion, but in getting to that conclusion, the author assumes information. Your job is to figure out what the author assumes to be true but doesn’t state directly in drawing the conclusion to the argument. Seeking-assumptions questions may look like these:

The argument in the preceding passage depends on which of the following assumptions?
The conclusion reached by the author of the preceding passage is a questionable one. On which of the following assumptions did the author rely?
The preceding paragraph presupposes which of the following?

Words like assume, rely, presuppose, depend on, and their derivatives usually indicate seeking-assumptions questions. Remember, these questions ask you to look for the ideas the author relies on but doesn’t state.

As you read seeking-assumptions questions, look for information that’s necessary to the argument but isn’t stated by the author. In these questions, the author always takes for granted something on which the entire argument depends. You just need to identify what that is. To do so effectively, choose an answer that links the existing premises to the conclusion. The assumption you’re seeking always bears directly on the conclusion and ties in with one or more premises, often with the last premise. Therefore, the best answer often contains information from both the last premise and the conclusion.

Example Women receive fewer speeding tickets than men do. Women also have lower car insurance rates. It is clear that women are better drivers than men.

The preceding conclusion is based on which of the following assumptions?

Men and women drive cars equal distances and with equal frequency.
Having lower car insurance rates indicates that one is a better driver than those who have higher rates.
Speeding tickets are equally awarded for violations without any gender bias on the part of police officers.

(A) I only

(B) III only

(D) II and III only

(E) I, II, and III

As always, read the question first. Because it references assumptions, we bet you figured out pretty quickly that it’s a seeking-assumptions question.

Next, read through the argument and try to figure out the assumption or assumptions the author makes in reaching the conclusion that women are better drivers. The author moves from the premises to the conclusion pretty quickly and assumes that fewer speeding tickets and lower car insurance rates indicate better driving skills. The author also assumes that men and women have equal driving experiences. Use this information to examine each of your options.

Look at Statement I first. It fits with your second observation that men and women experience equal driving situations, so eliminate any answer choices that don’t include Statement I. This means that you can get rid of Choices (B) and (D), which leaves you with Choices (A), (C), and (E).

Tip Before you continue reading through your options, examine the remaining answer choices. You’ll see that it’s best to examine Statement II next, because if it’s true, you won’t even have to read Statement III; you’ll know the answer is Choice (E). You have to read Statement III only if you determine that Statement II isn’t an assumption. (For more about strategies for answering Roman numeral questions, see Chapter 2.)

The information in Statement II links the author’s last premise, that women have lower insurance rates, to the conclusion that women are better drivers. Thus, Statement II is also correct. You can eliminate Choices (A) and (C), and by process of elimination, the answer must be Choice (E). If you read through Statement III, you’ll confirm that it, too, is an assumption the author makes about men and women having an equal playing field in the driving game.

If you find seeking-assumption questions to be tricky, try arguing the opposite position. For example, in the sample question, you could’ve taken the opposing view, that men are better drivers. This means you’ll be looking for ways to undermine the conclusion. If you assume the premises to be true, the best way to attack the conclusion is to show that the author assumes things that aren’t true. For example, you may argue that men have more accidents because they drive more, they get more tickets because police are less forgiving with male speeders, and they have higher car insurance rates because they drive more-expensive cars. Those counterarguments expose the author’s assumptions!

Using your noggin to make inferences

Critical reasoning inference questions ask you to make an inference (using inductive reasoning) based on the argument in the passage. Making-inferences questions are pretty easy to recognize because they usually include the word infer, such as the following examples:

Which of the following statements can be correctly inferred from the preceding passage?
Which of the following can be inferred from the preceding statements?

The key to answering these questions correctly is to know that they usually ask you to make an inference about one of the premises in the argument rather than about the entire argument or the conclusion. Because these questions usually deal with the premises and not the conclusion, you should choose an answer that makes a plausible inference about one or more of the premises. Like the correct answer choices for the drawing-conclusions questions, the best answers to this type of question don’t go beyond the scope of the information provided in the paragraph. Here’s what one looks like.

Example The highest-rated television shows do not always command the most advertising dollars. Ads that run during shows with lower overall ratings are often more expensive because the audience for those shows includes a high proportion of males between the ages of 19 and 34. Therefore, ads that run during sporting events are often more expensive than ads running during other types of programs.

Which of the following can properly be inferred from the preceding passage?

(A) Advertisers have done little research into the typical consumer and are not using their advertising dollars wisely.

(B) Sports programs have higher overall ratings than prime-time network programs.

(C) Advertisers believe males between the ages of 19 and 34 are more likely to be influenced by advertisers than are other categories of viewers.

(D) Advertising executives prefer sports programs and assume that other Americans do as well.

(E) Ads that run during the biggest sporting events are the most expensive of all ads.

You know you’re dealing with an inference question before you read through the argument because you’ve read the question first and it contains the word inferred. Focus on the premises of the argument as you read it. Then look through the answer choices and eliminate any that don’t address one of the premises or that present inferences that require additional information.

The argument says nothing about advertising research or whether the particular advertising practice is wise, so you can eliminate Choice (A) immediately. You’re stretching beyond the scope of the information if you infer that advertisers are unwise. Likewise, Choice (D) mentions the preferences and assumptions of advertisers, but none of the premises discuss advertisers, so you can get rid of Choice (D). The inference in Choice (E) relates to the conclusion rather than any of the premises, so you can probably eliminate it right away. Furthermore, just because sporting events ads are “often more expensive” than other ads doesn’t necessarily mean that they’re always the most expensive. This leaves you with Choices (B) and (C).

Choice (B) contradicts information in the argument. The author implies that some sporting events have lower overall ratings even though they have higher advertising rates. You’re left with Choice (C). You need an explanation for the information in the second sentence that states that advertising is often more expensive for lower-rated shows viewed by males who are between 19 and 34 years old. This practice would be logical only if males of these ages were more susceptible to advertising than other groups. It makes sense that Choice (C) is the correct answer.

Warning Remember to check your outside knowledge about the critical reasoning subjects at the door! You may know that Super Bowl ads are the most-expensive ads, which may tempt you to pick Choice (E). Using your own knowledge rather than what’s expressly stated in the test questions will cause you to miss questions that someone with less knowledge may answer correctly.

Making your way through method-of-reasoning questions

Method-of-reasoning questions are the rarest form of GMAT critical reasoning question types. This type of question either directly asks you what type of reasoning the author uses to make an argument or, more often, asks you to choose an answer that uses the same method of reasoning as the argument. You may see method-of-reasoning questions phrased like these:

Which of the following employs the same method of reasoning as the preceding argument?
The author’s point is made by which method of reasoning?
David’s argument is similar to Katy’s in which of the following ways?

The two types of method-of-reasoning questions may seem different, but each of them asks you to do the same thing: to recognize the type of reasoning used in the argument.

For the purposes of the GMAT, the methods of reasoning are as follows:

Deductive, which is reaching a specific conclusion from general premises
Inductive, which is drawing a general conclusion from specific premises and includes the following methods:
- Analogy, which shows that one thing is sufficiently similar to another thing such that what holds true for one is true for the other
- Cause and effect, which shows that one event resulted from another
- Statistics, which uses population samples (surveys) to reach conclusions about the population as a whole

Questions that ask you to specifically choose what kind of reasoning the author uses are straightforward, so we focus on the other type of question, which asks you to choose an answer that mimics the reasoning method of the given argument. When you know you’re dealing with this type of question, you just need to focus on the way the author makes the argument to make sure you choose an answer that follows the logic most exactly.

Don’t choose an answer just because it deals with the same subject matter as the given argument. These choices are often traps to lure you away from the answer that more exactly duplicates the author’s logic but addresses another topic.

It doesn’t matter whether the argument makes sense. If the given argument isn’t logical, pick an answer choice that isn’t logical in the same way.

You may focus on the method of reasoning better if you substitute letters for ideas in the argument. For example, say you’re presented with this argument: “Balloons that contain helium float. Jerry’s balloon doesn’t float, so it contains oxygen rather than helium.” You could state this logic with letters like this: “All A (helium balloons) are B (floaters). C (Jerry’s balloon) isn’t B (a floater), so C isn’t A.” Then you can apply that formula to your answer choices to see which one matches best.

Some of the reasoning methods may be as obscure as the one in this sample question.

Example A teacher told the students in her class, “The information that you read in your history book is correct because I chose the history book and I will be creating the test and assigning your grades.”

The reasoning in which of the following statements most closely resembles that of the preceding argument?

(A) The decisions made by the Supreme Court are just because the Court has the authority to administer justice.

(B) The people who have fame are famous because they deserve to be famous.

(C) Those who play sports get better grades because of the link between the health of the body and the health of the mind.

(D) Because my favorite teacher chooses to drive this kind of car, I should as well.

(E) Of 100 professors surveyed, 99 agree with the conclusions reached by the scientist in his paper on global warming.

Reading the question first tells you that you’ll have to analyze the way the author reaches the conclusion in the argument. As you read, you find that this illogical cause-and-effect argument states that information is correct because someone in a position of authority (the teacher) says so, so you need to find an equally illogical argument based on power and authority.

Because this is a cause-and-effect argument, you can eliminate any choices that don’t use cause and effect to reach a conclusion. All choices contain an element of cause and effect except Choice (D), which presumes an analogy between a favorite teacher and the writer, and Choice (E), which uses statistical evidence. (Note that just because Choice [D] also concerns a teacher doesn’t automatically make it the correct answer.) Disregard Choices (D) and (E) and examine the other three choices.

Among Choices (A), (B), and (C), the only choice that uses power to justify a cause-and-effect relationship is Choice (A). Choice (B) is faulty because it uses circular reasoning, which means it uses its conclusion as a premise, instead of using power to advance its position. Choice (C) doesn’t work because its logic isn’t necessarily faulty. Instead, it relies on a logical correlation between physical health and intellectual prowess. Therefore, Choice (A) is the answer that most nearly matches the kind of reasoning in the original argument.

Critical Reasoning Practice Questions and Answer Explanations

With practice, you’ll probably find that critical reasoning questions become some of the easiest question types to master in the GMAT verbal section. To master your approach, work through these practice questions and read through the answer explanations.

Critical reasoning practice questions

This set of 11 critical reasoning practice questions gives you a taste of what to expect from this verbal question, which tests your ability to analyze arguments. To mimic the approximate amount of time you’ll have to answer critical reasoning questions on the actual exam, try to answer these 11 questions in about 18 minutes. Answer each question based on the passage that precedes it, and choose the best answer from the five answer choices provided.

Don’t expect to see letters before the answer choices on the computerized GMAT. Each answer will have an oval next to it that you select by clicking on it. We’ve put letters next to the answers in this practice section to make it easier to discuss the answer in the explanations that follow the questions.

1. It seems that Americans are smarter than they were 50 years ago. Many more Americans are attending college now than in the past, and the typical entry-level job in business now requires a college degree.

Which of the following statements, if true, would most seriously weaken the argument in the preceding paragraph?

(A) High school courses are more rigorous now than they were in the past.

(B) Tuition at colleges and universities has more than tripled in the past 25 years.

(D) Businesses are not requiring as high a level of writing or math skills as they did in past decades.

(E) Many of the skills and concepts taught in high school 50 years ago are now taught in college.

Questions 2 and 3 are based on the following argument.

Rachel: The legal drinking age in America should remain at 21, because teens have not yet reached an age where they are able to consume alcohol responsibly. Additionally, the actions of 18-year-olds are more likely to be imitated by teens aged 15 to 17 than are the actions of those who are significantly older, so lowering the drinking age to 18 would also result in increased alcohol consumption by younger teens trying to emulate the actions of their older peers.

Mackenzie: The drinking age in America should be lowered to 18, because keeping it at 21 has not only failed to curb teen drinking but has encouraged those teens who do drink to do so in private, uncontrolled environments where they are more prone to life-endangering behavior. Many youths in European countries drink from an early age, and those countries have substantially fewer alcohol-related problems than we do in America.

2. Which of the following, if true, would most significantly weaken Mackenzie’s argument?

(A) The idea that Europeans and other nations with low or no minimum drinking ages do not have alcohol-related problems is a myth.

(B) If Americans are allowed to give their lives for this country at age 18, then they should be considered old enough to make the proper decision as to what to put in their bodies.

(D) In European culture, youths are taught at an early age that it is acceptable to either abstain from alcohol entirely or drink in moderation and that it is never acceptable for them to abuse alcohol, regardless of their age.

(E) European youths are just as likely as American youths to drink in private, uncontrolled environments.

3. Rachel’s argument is based on which of the following assumptions?

(A) Those who have reached the age of 21 are able to consume alcohol more responsibly than those who are 18.

(B) When European teenagers consume alcohol, they do so in public, controlled environments.

(D) The impressionability of one’s actions on others should not be a consideration when deciding the legal age to consume alcohol.

(E) Consuming alcohol in private, uncontrolled environments is not more dangerous than consuming alcohol in more public environments, such as bars or restaurants.

4. A recent census of all American females revealed that the current average age that females in America marry is 27. The average age that females have their first child is also 27. According to a census taken 20 years ago, the average ages that females married and had their first child were 23 and 25 years, respectively.

If the information recorded in the two censuses is true, which of the following must also be true about American females?

(A) Currently, more females are having their first child before they marry than they did 20 years ago.

(B) On average, females are currently waiting longer to have their first child than they did 20 years ago.

(C) Females today are more likely to complete their education before getting married and having children than they were 20 years ago.

(D) On average, females had larger families 20 years ago than they have today.

(E) Twenty years ago, most females waited at least two years after they were married to have their first child.

5. Continuous technological advances are critical to many types of business, because they allow machines to do the work previously done by humans — and they don’t have to be compensated. Banking executives are always looking for ways to cut costs, so they support a heavy emphasis on automated technology in the workplace. Yet what customers look for most in their banks is to be recognized by their teller and feel a sense of familiarity and friendliness upon entering, so the reliance of banks on machines should be minimized, rather than exacerbated.

Which of the following best outlines the main idea of the argument?

(A) Banks should reduce their dependence on technology.

(B) Bank patrons desire personal attention.

(D) Bank executives are a greedy bunch.

(E) Bank automation is inevitable.

6. A school board candidate has indicated that cheating through the use of cellphones in the classroom is on the rise this year and has proposed a ban on cellphones in schools altogether. School officials cite only a marginal increase in the number of students who cheat this year in comparison to the last two years, so this is just a ploy to make voters think a quality education is his top priority.

Which of the following, if true, best strengthens the conclusion of the preceding argument?

(A) The school board candidate has continuously voted down proposals to increase the budget for area schools.

(B) The school board candidate has continuously voted in favor of budget increases for area schools.

(C) This year, schools in the district have smaller class sizes and better student/teacher ratios than they have had in past years.

(D) The ratio of teachers to number of students has decreased significantly over the past several years because of a growth in number of students district-wide without a concomitant rise in the number of teachers to accommodate the increase.

(E) The school board candidate has a daughter who attends a school in the district, and he does not want her to own a cellphone.

7. Springfield is the first city to ban fast-food advertisements marketed specifically toward children. Although eating fast food has been linked to weight gain, banning these advertisements will do little to curb childhood obesity, and it should be the job of the parent, not the government, to tell children what to eat.

The argument would be most weakened if which of the following were true?

(A) Families are increasingly relying on the fast-food industry for financial reasons and will continue to frequent these establishments on their own terms, regardless of their children’s preferences.

(B) Studies indicate that, generally speaking, adults tend to be more influenced by advertising than children.

(C) If children learn that adults are trying to limit their fast-food intake, they will want to consume fast food even more.

(D) Those opposed to fast-food marketing geared toward children are welcome to buy airtime for their cause, too.

(E) Watching an advertisement has been shown to increase one’s desires for a product, particularly when the product is a food item.

8. Patients who feel they have a good relationship with their doctors generally show more improvement in their health than those who lack a connection with their doctors. Patients who like their doctors show improved emotional well-being, are less anxious about their symptoms, and are more likely to follow doctors’ advice.

Which one of the following, if true, would provide the most support for the argument?

(A) Patients are more likely to take legal action against a doctor for malpractice if they believe that the doctor failed to establish a connection with them during their office visits.

(B) Recently, medical schools and health insurers have taken measures to improve doctor-patient communication.

(C) Doctors who work in stressful environments are much less likely to take the time to connect with patients than doctors in more relaxed settings.

(D) The average physician spends about 15 minutes with each patient during routine office visits.

(E) A large number of studies have confirmed that the more anxious a patient is, the more protracted his or her recovery from a medical condition is.

9. The legislature is considering a law banning the use of cellphones by people who are driving a moving car. Drivers texting and talking while driving are distracted by their phone conversations and can’t give their full attention to driving their vehicles. Banning the use of cellphones by drivers will make the roads safer.

The argument depends on assuming which one of the following?

(A) A study by a sociologist has shown that the use of cellphones is occasionally a contributing factor in traffic accidents.

(B) The proper role of the legislature is to enact laws that protect the safety of drivers and passengers in automobiles.

(C) Drivers who hold their cellphones in their hands are more distracted than drivers who use a hands-free headset or speakerphone while driving.

(D) Because drivers talking and texting on cellphones are distracted, they are more prone to getting into accidents.

(E) Many drivers engage in behavior that distracts them from their driving, such as eating, adjusting the radio, reading maps, and talking on cellphones.

10. Many Americans do not take all the vacation time to which they are entitled. There are several reasons for this: They feel that they are indispensable at work, they fear the resentment of co-workers, or they dread discovering that their workplaces can actually function perfectly well without them. This is a mistake; vacation time gives workers a chance to rest, recover, and gain perspective that in turn can lead to more creativity and better performance at work.

The claim that many Americans don’t take all the vacation time to which they are entitled plays which one of the following roles in the argument?

(A) It is a recommendation of a policy that the American workplace should implement.

(B) It is evidence of the author’s claim that vacation time gives workers a chance to rest.

(D) It is a statement of a principle that the author wishes all people would observe.

(E) It is a statement of fact about which the author expresses an opinion.

11. A large Southern state university has changed its teaching practices. Formerly, instructors without PhDs taught most introductory courses; now professors with PhDs will teach all introductory classes. That means the average class size will increase from 44 students per class to 600 per class, but overall the students’ learning experience should improve.

Which one of the following is an assumption required by this argument?

(A) Requiring professors with PhDs to teach all introductory classes will mean that the university must hire more faculty with doctorates.

(B) Students tend to participate in smaller classes more than they do in large lectures, even when the lectures are supplemented by weekly discussion sections.

(C) Major private universities already have implemented a format in which professors with PhDs teach all introductory classes as large lectures.

(D) A class taught by a PhD, even in a lecture format with hundreds of students, is a better learning environment than a smaller class taught by an instructor without a PhD.

(E) Services that rank colleges and universities usually consider the percentage of classes taught by PhDs when computing rank.

Answer explanations

E. Read the question first so you know what to focus on in the passage. Because this question asks you to weaken the argument, you know you need to figure out what the conclusion is and what kind of reasoning the author uses in moving from the premises to the conclusion.

When you examine the argument, you may notice that the conclusion actually comes first. The author concludes that Americans are smarter than they were 50 years ago and does so by contrasting current college participation and entry-level job requirements with those of the past. The method of reasoning is similar to analogy, except instead of showing similarities between Americans now and 50 years ago, the author shows the differences. To weaken the conclusion that Americans are smarter today, you need to find the answer choice that shows that things really aren’t all that different today than they were 50 years ago.

First, eliminate answer choices with irrelevant information. Neither college tuition rates nor class size and curriculum have anything to do with levels of intelligence, so Choices (B) and (C) are wrong. Plus, you’re looking for an answer that shows that things aren’t much different between now and yesterday, and Choices (B) and (C) accentuate the difference.

Then, get rid of any answer that tends to strengthen rather than weaken the conclusion that Americans are smarter. More-difficult high school courses seem to indicate that Americans may indeed be smarter, so disregard Choice (A). This leaves you with Choices (D) and (E), and your job is to choose the one that shows that now and then aren’t all that different. Not only does Choice (D) demonstrate a difference between the eras, but it also refutes the premise that businesses are looking for the higher skill levels of a college education.

The correct answer must be Choice (E). If skills that were part of the high school curriculum 50 years ago are now offered in college, actual education hasn’t changed all that much from then to now. Americans must now attend college to acquire the high school skills of earlier times, and businesses need to require college degrees to make sure their employees have the same skills that high school students had in the past. If the skill levels are the same, Americans aren’t really any smarter than they were 50 years ago.

You must know precisely what point a paragraph is arguing before you can strengthen or weaken that argument. Take the time to understand the premises, conclusion, and method of reasoning so you can quickly eliminate answer choices and accurately select the best answer. When you really understand the argument, attacking or defending it is fairly easy.
E. First, a quick review of Mackenzie’s argument indicates that she is in favor of lowering the drinking age, not opposed, so you can quickly eliminate any answer choices that include support for doing so, such as Choices (B) and (C), because those choices actually strengthen Mackenzie’s argument.

Now, determine which of the remaining options best weakens Mackenzie’s argument that the legal drinking age should be lowered. The remaining answers focus on Mackenzie’s premise that because European countries have lower drinking ages and fewer problems with alcohol, lowering the drinking age in America would likewise lead to fewer alcohol-related problems. She makes her argument based on an analogy between Europe and America, so weaken her contention by showing that Europe and America are substantially similar in their approach to teenage drinking. It may sound surprising to weaken an analogy with a similarity, but in this case Mackenzie’s analogy seeks to liken the alleged present state of affairs in Europe to the supposed future state of affairs in America if the American drinking age is lowered. Showing a similarity between present-day Europe and present-day America can therefore weaken the argument that a change in the drinking age will reduce alcohol-related problems in America.

Mackenzie doesn’t say that European countries have no alcohol-related problems, just that there are fewer, so Choice (A) is irrelevant to her argument. Choice (D) provides a concrete difference between European and American culture that reveals why European teens tend to be more responsible than American teens when it comes to alcohol consumption, so this is an answer choice that seems to lend support to Mackenzie’s argument that a lower drinking age won’t result in less-responsible drinking among American teens. On the other hand, Choice (E) reveals a similarity between European and American youth, which best serves to weaken Mackenzie’s analogy between the lower drinking age in Europe and the proposed lower drinking age in America. If both European and American youths drink in private, uncontrolled environments despite the difference in the drinking ages of the two cultures, it’s unlikely that changing the drinking age in America will affect the behavior that Mackenzie claims is dangerous (drinking in private).
A. Rachel argues for retaining the current legal drinking age of 21. She bases her conclusion on the premises that younger drinkers are more likely to influence the behavior of 15- to 17-year-olds and that teens haven’t reached an age where they can drink alcohol responsibly.

To find the correct answer to questions that ask for an assumption, look for the answer choice that links one or more of the premises to the conclusion. Eliminate answer choices that don’t relate to at least one of the premises of the argument.

Choices (B) and (E) relate to one of Mackenzie’s premises, so it’s unlikely that they would reveal one of Rachel’s assumptions. Cross out those two answers on your noteboard.

You can also check off Choice (D) because it contradicts Rachel’s premise that the effect an 18-year-old’s alcohol consumption can have on younger peers is an important consideration in determining the legal drinking age. It’s also unlikely that Choice (C) is correct because Rachel doesn’t make comparisons regarding the impressionability of teens based on their ages. Her premise is that younger teens are more likely to be influenced by 18-year-olds than 21-year-olds. Furthermore, Choice (C) doesn’t link one of Rachel’s premises to her conclusion in the way that Choice (A) does.

If Rachel concludes that the legal drinking age must remain at 21 because younger drinkers don’t consume alcohol responsibly, she must think that 21-year-olds have achieved some level of responsibility that’s greater than those who are younger. Choice (A) links the relevance of one of Rachel’s premises (a lower level of responsible drinking) to her conclusion that people who are younger than 21 shouldn’t be able to legally consume alcohol. So the correct answer is Choice (A).
B. This question asks you to come up with a conclusion based on the information in the paragraph.

Notice that the question asks you for what must be true rather than what could be true. So you can cross out any answers that aren’t absolutely true given the data in the paragraph.

All you know from the paragraph is the average marrying age for females today and 20 years ago and the average age that females have their first child today compared to 20 years ago. The paragraph says nothing about the number of children females have or had, so you can easily wipe Choice (D) out of contention. Furthermore, the paragraph provides no explanation for why the data has changed over the years, so you can’t know the reason that the average age has increased. So Choice (C) can’t be right.

Don’t choose an answer based on an assumption or your own experience. The paragraph merely reports data instead of commenting on it, and it treats the age of marrying and having one’s first child as two separate statistics. You can’t make assumptions about how the two sets of data are related.

That means that Choice (A) doesn’t have to be true. Just because the average age for marrying and having a first child are currently the same doesn’t mean that more American females are having their first child before they marry. For example, the increased marrying age could be the result of females who marry when they’re older and have no children. Eliminate Choice (E) for the same reason. You can’t assume from these limited statistics that the females who are 23 when they marry are the ones who are having their first child at 25. There are too many other variables in the population.

The only thing you know for sure is that, because the average age for having a first child has risen over the last 20 years, on average, females are having their first child at a later age than they did 20 years ago. Choice (B) is the only answer that must be true.
A. Asking for the main point of an argument is another sneaky way of getting you to pick out the conclusion. This paragraph makes it easy for you because the conclusion follows the so in the last sentence: Banks should rely less on machines. The first sentence of the argument equates machines with technological advances, which means that you can say that the main point is that banks should rely less on technology, Choice (A).

Choices (C), (D), and (E) require you to make assumptions that aren’t supported by the argument. Because you read newspaper headlines, you may think that Choice (D)’s assertion about the avarice of bank executives is a foregone conclusion, but, alas, it isn’t mentioned in the argument. (You should also have been alerted by the debatable word inevitable in Choice [E]). The paragraph does suggest that bank patrons want personal attention (Choice [B]), but this statement is a premise rather than the conclusion. So the correct answer is Choice (A).
D. The first step to answering any question that asks you to strengthen a conclusion is to figure out exactly what that conclusion is. In this case, the paragraph argues that the candidate’s proposal to ban cellphones in schools is a campaign strategy to make voters think he cares about the quality of education. The argument is based on the statistic that the increase in the number of students who cheat has been insignificant. To support the author’s argument, find the answer that best supports the contention that cheating really hasn’t increased all that much.

Eliminate choices that don’t pertain to the author’s argument. You can disregard Choices (A) and (B). The argument is concerned with the implications surrounding a cellphone ban, not the candidate’s position on a budget increase. You’re assuming too much (or relying on your own opinion) to make a determination of whether the candidate’s vote for or against a budget increase has anything to do with education quality.

Choice (E) indicates that a reason other than cheating may be the reason the candidate wishes to impose the cellphone ban, but that absurd personal reason doesn’t support the author’s argument that the candidate is proposing the ban for political reasons.

The answer must be either Choice (C) or Choice (D). Both deal with the number of actual students in the district, so they may reflect on the validity of the candidate’s claim that cheating has increased and the author’s claim that it hasn’t. Having smaller class sizes tells you nothing about the overall number of students. The district could have hired more teachers to accommodate the same number of students. The only answer that relates to the cheating statistic is Choice (D). The marginal increase in cheating could be due to an increase in number of students rather than an increase in cellphone cheating, which supports the author’s argument that the candidate’s reason for banning cellphone use is unfounded.
E. The implication is that the advertising ban is designed to curb childhood obesity. The author states that this ban won’t work, which suggests that the author thinks that the fast-food advertisements don’t cause childhood obesity. To weaken this argument, show that the advertisements do indeed lead to obesity. If it’s been proven that watching an ad increases one’s desire for something, then banning the ads would reduce the desire for fast food that produces weight gain in children. Choice (E) weakens the author’s argument by showing that the advertisement ban will indeed curb childhood obesity. Choice (A) seems to strengthen the author’s argument, and Choices (B), (C), and (D) deal with tangents that don’t relate to whether the advertisement would be effective in curbing childhood obesity. The correct answer is Choice (E).
E. The argument claims that patients do better when they feel a connection to their doctors; the premises are three factors that result from liking one’s doctor. To support this argument, you need to find statements that link those factors with health improvements. Choice (A) doesn’t help. It illustrates the danger of people not liking their doctors but doesn’t prove the point that patients who like their doctors are healthier. Choice (B) may suggest that improving doctor-patient communication is desirable, but it doesn’t specifically link improved communication to improved patient health. Choice (C) presents a reason for poor doctor-patient communication but doesn’t show how that affects patient health. Choice (D) provides evidence of how the average doctor doesn’t have a good relationship with patients, but it doesn’t show the results of good doctor-patient rapport. Choice (E) does support the conclusion by linking one effect of liking a doctor (less anxiety) to a greater improvement in health. Choice (E) is correct.
D. You’re looking for an assumption. Assumptions connect the premises to the conclusion. The conclusion that if drivers can’t use cellphones, the roads will be safer is based on the evidence that drivers on phones are distracted; the author assumes that distracted drivers are unsafe drivers. (Yes, that’s obvious, but the author doesn’t explicitly say what the connection is, so it’s an assumption.) Choice (A) is tricky and could be a possible answer if you were asked to support the legislator's argument, but information about the results of a specific cellphone use study is way too specific to be the legislator’s assumption. Assumptions are rarely based on particular statistical data. See whether you can find a better answer. Choice (B) is wrong; the author probably does assume that this is the legislature’s job, but this assumption isn’t necessary to the specific argument connecting distraction and road safety. Choice (C) doesn’t work; the author isn’t concerned with distinctions among types of cellphones users. Choice (D) is something the author assumes — it explains the connection between cellphones and distracted drivers and dangerous roads. Choice (E) contains mostly irrelevant details about other behaviors, and to the extent it addresses drivers on cellphones, it just repeats evidence the argument already explicitly states. Choice (D) is the best answer.
E. The claim in the question is a statement of fact in the first sentence that the speaker explores more thoroughly, concluding with the statement that it’s a mistake. She’s not suggesting that it’s a good thing, so Choices (A) and (D) are wrong. It’s not evidence, so Choice (B) is wrong. Her actual conclusion is that refraining from taking vacation is a mistake, so Choice (C) is wrong. The claim is a statement of fact that provides the background information for the author’s opinion about what Americans should do with their vacation time, so Choice (E) is correct.
D. The author concludes that having classes taught by PhDs instead of instructors improves students’ learning experience, so he must assume that PhDs, even in very large classes, are somehow better at teaching than instructors in smaller ones. Choice (A) isn’t his assumption. In fact, the reference to increased class sizes suggests that the university won’t be hiring more faculty. Choice (B) contradicts the author’s conclusion by suggesting that student participation is a good thing. Choice (C) is interesting information but isn’t essential to the conclusion about the practices of the particular Southern state university in the argument, especially because it doesn’t mention students’ learning experiences. Choice (D) looks like the right answer. The author does seem to think that a class taught by a PhD is somehow superior, which explains why he thinks the change would benefit students. Choice (E) explains why the university may want to increase classes taught by PhDs, but it doesn’t explain how that would benefit students. Choice (D) is correct.