Four chests (Alpha, Beta, Gamma, Delta) each hold either gold or silver. Alpha has gold if and only if Beta has silver. Beta has gold if and only if Gamma has gold. Gamma and Delta do not both have silver. Delta has silver if and only if Alpha has silver. How many chests contain gold?
2 chests
If Alpha has gold, Beta has silver, Gamma has silver, and Delta has gold (2 gold chests). If Alpha has silver, Beta has gold, Gamma has gold, and Delta has silver (2 gold chests). In both consistent cases, exactly 2 chests contain gold.
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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