A squirrel hides acorns in three colored jars: red, blue, and green. Only one jar holds the acorns. A label on the red jar says 'The acorns are here.' A label on the blue jar says 'The acorns are not here.' A label on the green jar says 'The acorns are not in the red jar.' If exactly one label is true, which jar holds the acorns?
The blue jar
If the acorns are in the blue jar: Label 1 (Red) is false, Label 2 (Blue) is false, and Label 3 (Green) is true ('not in red'). This satisfies the rule that exactly one label is true. Any other location makes multiple labels true.
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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