You have three closed boxes labeled 'Apples', 'Oranges', and 'Mixed'. Every single box is incorrectly labeled. You pick one fruit from one box without looking inside. Which box must you pick from to correctly identify the contents of all three boxes?
The box labeled 'Mixed'
Since every label is wrong, 'Mixed' contains either only apples or only oranges. If you draw an apple from 'Mixed', that box is 'Apples'. The box labeled 'Oranges' cannot contain oranges (mislabeled) nor apples (just found), so it must be 'Mixed'. The box labeled 'Apples' must then be 'Oranges'.
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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