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"You have a 100 coins laying flat on a table, each with a head side and a tail side. 10 of them are heads up, 90 are tails up. You can't feel, see or in any other way find out which side is up. Split the coins into two piles such that there are the same number of heads in each pile."

This question appeared on 25 Tough Questions Asked In Apple Interviews on MENSXP website.


marked as duplicate by Ankoganit, kaine, Glorfindel, JMP, Rubio Jan 26 '17 at 6:21

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Split into a pile of 90 coins, and a pile of 10 coins. Flip those 10 coins over, and the question is solved.

This is a very well-known problem.

  • $\begingroup$ bro spoilers... $\endgroup$ – greenturtle3141 Jan 26 '17 at 6:21

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