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One item is filed under this topic.
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A magic/math trick |
2009-12-04 |
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From Valentin:
What is the explanation for the following math trick: you think of any four digit number add those digits take that sum and subtract it from the first number then you say three of those new numbers in any order and the other person guesses the last digit.
How does he do it?
Answered by Claude Tardif. |
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