A merchant has three sacks. One contains only gold coins, one contains only silver coins, and one contains a mix of gold and silver. All three sacks are labeled incorrectly. The merchant lets you draw a single coin from just one sack to fix all the labels. Which sack do you draw from?
The sack labeled 'Mixed'
Every sack is labeled incorrectly. Therefore, the sack labeled 'Mixed' cannot actually contain mixed coins; it must contain either all gold or all silver. By drawing one coin from the 'Mixed' sack, if you pull gold, that sack is actually Gold. Since the other two sacks are also mislabeled, you can instantly deduce the contents of all three.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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