12 Balls Problem


You have 12 balls (of any kind), one ball either lighter or heavier than the other 11. A scale is provided to you but only three weighs are allowed. How can you possibly figure out which is the odd ball?

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Reader Comments

six balls on each side, take the heavier
thres balls on each side, take the heavier
weigh 2 of the last 3, take the heavier
if they are even, the non-weighed on is different

This is not so easy.
We don’t know about the odd ball, it may be heavier or lighter.
Try to solve it again…Good luck

The answer is correct. Your question asked how to determine which was the odd ball, it did not ask to determine if the odd one was lighter or heavier.

The answer is wrong. six balls on each side, take the heavier

three balls on each side. take the heavier. what if the odd ball is in the lighter pile. get the error

good luck.

first result of the google search for “12 Balls Problem”:
http://www.curiouser.co.uk/puzzles/12balls.htm

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