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Question:

You have nine ball-bearings riddle?

You have nine ball-bearings, all of the same size but one slightly heavier than the others, though not enough to be detected by holding them. You have some balance scales and are allowed to do only two weighing of any number of ball bearings. How do you find the heavy one?P.S. please answer this so I could get 5 extra points in my exam .lol thanks!!!

Answer:

Weigh three ball bearings against another three ball bearings. If one side goes down then you know the heavy one is one of those three. If the scale balances then it is one of the ones you didn't weigh. Weight two of the three containing the heavy ball against each other. If one side goes down then it is the heavy one. If the scales balance then the heavy one is the one you didn't weigh.

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