Weighing Bags of Coins - Solution

Puzzles -> Measuring Puzzles

The Puzzle: You have eight bags, each of them containing 48 coins.

Five of these bags contain only true coins, the rest of them contain fake coins.

Fake coins weigh 1 gram less than the real coins. You do not know what bags have fake coins and what bags have real coins. You can use a scale with precision up to 1 gram. Making only one weighing and using the minimum number of coins, how can you find the bags containing the fake coins?

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The Solution . . .

Take out 0 (no coin from the first bag), 1 (one coin from the second bag etc.), 2, 4, 7, 13, 24, 44 coins (from the last, 8th, bag).

Each triple is unique enabling an easy way to identify the bags with fake coins (using only 95 coins).

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