You are blindfolded before a table. On the table are a very large number of pennies. You are told 128 of the pennies are heads up and the rest are tails up.

How can you create two subgroups of pennies, each with the same number of heads facing up?

(In reply to solution by SilverKnight)

If you are only supposed to find two groups at some point in time ("keep trying until you get it right"), I don't like this problem very much.

Since the problem doesn't say that the two subgroups involved have to include the entire set of pennies, just take two. If they're both heads or both tails, you're done; if not, just flip one over.

I hope there is a more satisfactory solution, although I don't see how, right now...

Posted by DJ on 2003-10-14 12:44:24