1 Ball is defected of of 8 can you find in 2 weighs?

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There are 8 balls. 7 of them weigh the same. 1 of them has a different weight, (you don’t know if it’s heavier or lighter).

How do you find the odd ball with 2 weighs?

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    Best answer

    NO, It is not possible.

    This can be explained by information theory. We need to extract 16 units of information (A ball may be light or heavy -2 units and it can be one of 8 balls). However, we gain just 3 units of information (light, heavy or equal).

    So, we need ceil[log3(16)] = 3 weighings.

    In the similar question you linked to, we had 24 units of information and so we needed ceil[log3(24)] = 3 weighing.

    ______________________________________________
    Answer Source – Simranjit Kohli, Googler

    Detective Expert Answered on 24th August 2015.
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