Match Math

May 11, 2019

RAY: Go and get a bunch of matchsticks. We'll wait. Okay. Time's up. A little piece of paper and a pen, with which you can represent matchsticks. The numerator of this fraction is going to be Roman numerals, okay? And the Roman numeral is 23, which is X-X-I-I-I.

Anyway, there are a bunch of matchsticks, and make your line. And then the denominator is going to be 7 in Roman numerals, which is V-I-I. And then an equals sign--it's a little equation--equals 2, which is represented by two matchsticks, two vertical matchsticks, I-I. Okay? Roman numeral 23, X-X-I-I-I, over Roman numeral 7, which is V-I-I, equals 2, which is I-I, capital. Obviously, this equation is wrong.

Your challenge is to move one matchstick and make the equation correct. Now, you cannot turn it in, you cannot take one matchstick, for example, and make it 22 over 7 does not equal 3. So, an "unequal" sign is not allowed.

So, the question is, How can you move one matchstick and make this into an actual equation?


RAY: OK? So, how can you move one matchstick to make the equation correct? Now, we're going to get a bunch of people to go, "Aw, man, this is bogus!" But...tough!

But I think the solution is elegant. You are going to take one away from the numerator.

So, instead of saying 23, it's going to be 22. And now you have 22 over 7, and with that one matchstick that you removed, a number should jump into your head.

Because 22 over 7 equals pi, and you're going to put that matchstick that you've removed from the numerator atop the 2 on the right side of the equation, and although it isn't quite accurate, you're going to make the symbol for pi, thus making the equation correct, and I think it's pretty good.

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