# Clue to Riddle #65: 9 Coins, 1 Odd one, 2 Weighings

65. There are 9 coins, all except one are the same weight, the odd one is heavier than the rest. You must determine which is the odd one out using an old fashioned balance. You may use the balance twice. Explain how this can be done.
It's always difficult to give clues to the quickie puzzles. But I would say this. Because we know, as fact, that one coin must be heavy it would be sufficient to eliminate coins 1 - 8 in order to prove that it is number nine....

That having been said, a good initial weighing would be 1,2 & 3 against 4,5 & 6.

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