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 re: solution
You are blindfolded... so you don't know (after taking two) whether or not they're both heads.
The point is... to be able to solve the problem WITHOUT looking, and without being told when you're right... rather to KNOW that you've succeeded without outside intervention.
And I think my solution does that.