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There is a table on which, a number of coins are placed. You also know that there are as many coins with Heads up, as many coins with Tails up. You are blind folded and there is no way to determine which side is up by rubbing, etc. Now you have to divide the coins into two equal piles(number of coins is even), such that number of coins with Heads up and Tails up in either piles be the same.

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In any partition into equal piles, the number of Heads in the first pile equals the number o fTails in the other, if that is what you are after ... – Hagen von Eitzen Feb 1 '14 at 13:26
up vote 7 down vote accepted

You first split the coins up into two equal piles. Then the number of heads in one pile is equal to the number of tails in the other and vice versa.

Then the next step is to turn every coin in one of the piles around. Then you'll have the same amount of heads/tails in each pile.

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