   How would you identify the heavier ball if you could use a two-pan balance scale only twice?

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There are 9 similar balls. Eight of them weigh the same and the ninth is a bit heavier.
How would you identify the heavier ball if you could use a two-pan balance scale only twice? posted Nov 20, 2014

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Divide the 9 balls into 3 groups of 3. Weigh two groups. now u get the group is the heavier ball in. now again choose 2 balls from this group and compare their weights. and u get the heavier ball answer Nov 21, 2014

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