Assume now that you have (n) coins. All the coins look the same and there is only 1 false coin, but now it is heavier than the true coins.
All true coins weigh the same amount. You may use a set of balance scales.
(a) Can you isolate the counterfeit in 3 weighings if (n=27)?
(b) Can you isolate the counterfeit in 4 weighings if (n=81)?
(c) What is the smallest number of weighings needed when (n=82) and when (n=80)?
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