SOLUTION: Prove that for any 8 natural numbers you can choose two of them so that their difference is divisible by 7.

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Question 1026899: Prove that for any 8 natural numbers you can choose two of them so that their difference is divisible by 7.

Answer by richard1234(7193)   (Show Source): You can put this solution on YOUR website!
By Pigeonhole principle, there are two natural numbers that leave the same remainder when divided by 7, so the difference between these two is divisible by 7.
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