The average of 11 numbers is 10. When one number is eliminated, the average of the remaining numbers is 9.3. What is the eliminated number?
The average of 9, 11, and 16 is equal to the average of 21, 4.6, and what number?
For the list of numbers {4, 5, 5, 6, 7, 8, 21}, how much greater is the mean than the median?
The sum of 8 numbers is 168. If one of the numbers is 28, what is the average of the other 7 numbers?
If the average of the list {5, 6, 6, 8, 9, x, y} is 6, then what is the value of x + y?
On 4 sales, Matt received commissions of $300, $40, $x, and $140. Without the $x, his average commission would be $50 lower. What is x?
The class mean score on a test was 60, and the standard deviation was 15. If Elena’s score was within 2 standard deviations of the mean, what is the lowest score she could have received?
Milo gets a $1,000 commission on a big sale. This commission alone raises his average commission by $150. If Milo’s new average commission is $400, how many sales has Milo made?
Grace’s average bowling score over the past 6 games is 150. If she wants to raise her average score by 10%, and she has two more games remaining in the season, what must her average score on the last two games be?
If the average of x and y is 50, and the average of y and z is 80, what is the value of z − x?
If x > 0 and the range of 1, 2, x, 5, and x2 equals 7, what is the approximate average (mean) of the list?
Among the list {1, 2, 3, 4, 7, 7, 10, 10, 11, 14, 19, 19, 23, 24, 25, 26}, what is the ratio of the largest item in Quartile 2 to the average value in Quartile 4?
N is a normally distributed set with a mean of 0. If approximately 2% of the observations in N are −10 or smaller, what fraction of the observations are between 0 and 5?
A college class is attended by Poets and Bards in the ratio of 3 Poets for every 2 Bards. On a midterm, the average score of the Poets is 60 and the average score of the Bards is 80.
| Quantity A | Quantity B |
| The overall average score for the class |
70 |
| x > 2 | |
| Quantity A | Quantity B |
| The median of x − 4, x + 1, and 4x | The mean of x − 4, x + 1, and 4x |
A is the set of the first five positive odd integers. B is the set of the first five positive even integers.
| Quantity A | Quantity B |
| The standard deviation of A | The standard deviation of B |