How Much for Twelve? The Confounding House Number Puzzler.

Aug 01, 2005

RAY: A man is waiting in line at a hardware store to buy letters that make up the number of his house. You know. For example --

TOM: T, H, R, E, E.

RAY: Right. But, by luck, there were three other guys ahead of him in line all doing the same thing. The first customer buys the number one. O, N, E. He pays two bucks. The next guy buys the number TWO, and pays three bucks. The third guy buys the number ELEVEN, and he pays five bucks.

Our protagonist is buying the number twelve.
RAY: Let's look at the word, "Twelve." And then let's look at the word, "Eleven." They share four letters: E-L-E-V.

So if you take that away from the 12, you get T-W left over.

If you take those same four letters away from 11, you have N-E left over. Now, let's go back to the first two guys.

TOM: I'm with you! This is great, keep going.

RAY: "One" cost two dollars, and "Two" cost three dollars. What have we learned? Now we don't know the cost of any of the letters individually. But we do know that a T and a W costs a dollar more than an N and an E.

As luck would have it, the T and W in "Twelve" are going to cost a dollar more than the N and the E in "Eleven." We know the whole of "Eleven" costs five bucks, so "Twelve" must cost six bucks.

Pretty good. Huh? And you could use higher mathematics to solve this!

TOM: Well, I was writing a series of simultaneous equations.

RAY: Who's our winner?

TOM: The winner this week is Meg Schneider from Boise, Idaho. And for having her answer selected at random from the freezer bag full of correct answers that we got, Meg is going to get a 26-dollar gift certificate to the Shameless Commerce Division at Now, isn't that exciting!

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