There are 10 barrels containing gold coins. In that, 9 barrels contains 1 gram gold coins and the other barrel contains 2 gram coins. Every coin looks to be same without any difference. As the barrels weigh more, so it cannot be lifted or moved from its place. There is a weighing machine which is allowed to weigh only once. How to find that which of the barrels contain 2 gram coins..?

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TopNewestTake n coins from the nth barrel. The deficiency from 110 grams is the number of the barrel with the 1 gram coins. For example, if the 6th barrel has the light coins, the coins will weigh 104 grams. 110-104 = 6. – John Chang · 3 years, 10 months ago

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2 solutions. You could first JUST OPEN THE BARRELS and select the one that has the most coins; or you could play with luck and guess with 2 random barrels assuming that one has 2 grams of coins. – Nathan Blanco · 3 years, 10 months ago

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