Three boxes numbered 1, 2, and 3 are on a table. One contains a gold coin. Box 1 says: 'The gold is in Box 2 or Box 3.' Box 2 says: 'The gold is in Box 1.' Box 3 says: 'The gold is NOT in Box 1.' If exactly one statement is TRUE, which box holds the gold coin?
Box 1
Test each box: 1) If Gold is in Box 1: Box 1 statement is False, Box 2 is True, Box 3 is False. Exactly 1 statement is True! 2) If Gold is in Box 2: Box 1 is True, Box 2 is False, Box 3 is True (2 Trues). 3) If Gold is in Box 3: Box 1 is True, Box 2 is False, Box 3 is True (2 Trues). Therefore, the gold coin must be in Box 1.
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: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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