51. The Equation
class: closer | impressiveness: 4/5 | factors: frustratingly simple, agonizingly hard | requires: a fistful of matches or toothpicks, open table space | watch full episode
This one’s a stumper of a puzzle‚ yet only uses 4th grade math. It’s also another one that I’m going to insist you actually try to solve before looking up the answer. With puzzles like these, the quicker you give the answer, the dumber they seem to be. In real life, I’ll often leave a puzzle like this to simmer for 20 or 30 minutes before giving up the answer, even if they promise me a beer for it.
The Effect: Using matches (or toothpicks), create the incorrect math equation 1+11+111=1111. Then challenge your friend to move only one match and make the equation true.
Make sure to point out that the 4 matches on the right side of the equation are correct; it’s only the left side that needs fixing. To be even more fair, point out that they can interpret the numbers as roman numerals, hash marks, or traditional Arabic numerals (in truth, all these extra options only serve to make the puzzle even harder).
Oh, and don’t let them pull the wise guy move of laying one match across the equals to make a “does not equal” sign!
Okay, Brian. I totally pulled out matches, set this up and spent 3 hours trying to solve this one. Now give me the answer before I punch you!