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The Mathematic Mistake

The Puzzler


TOM: Well, you know as I was driving home last week, the answer came to me in a flash.


RAY: Are you ten?


TOM: And I'm more than ten. I'm ten to a power. I'm ten to the N. What occurred to me was C is 121 no matter what you do that. Any power is going to end in a one. And no matter what you do to the other ones, you can't make them come out to add up to one. You can't do it.


RAY: There you go. And that's exactly what the kid saw. He said 91 to the Nth power is going to end in one.


Fifty-six to the Nth power is going to end in six. Six plus one has not to equal seven.


TOM: Not one.


RAY: The one’s digit is going to be a seven. So the one's digit of the 121 to the Nth power has got to be seven and it can't be.


TOM: It can't be.


RAY: Who's our winner this week?


TOM: The winner is Mrs. Donna Marie Markey. Wow, she gave us a whole name like that. Donna Marie Markey from Albany, New York.


 

[ Car Talk Puzzler ]

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