You stand before three closed boxes labeled 'Apples', 'Oranges', and 'Mix'. You are informed that every single label is incorrect. You can pick only one box, pull out one fruit without looking inside, and observe it. How can you determine the correct contents of all three boxes?
Pick a fruit from the box labeled 'Mix'
Since the 'Mix' label is wrong, this box contains either only apples or only oranges. If you draw an apple, the 'Mix' box must actually be 'Apples'. The box labeled 'Oranges' cannot contain oranges (wrong label) and cannot contain apples (already found), so it must be 'Mix'. The box labeled 'Apples' must then be 'Oranges'. If you draw an orange instead, the inverse reasoning identifies 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: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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