In a drawer, there are 10 matching black socks and 10 matching white socks all jumbled together in the dark. What is the minimum number of socks you must pull out to guarantee you have at least one matching pair of any color?
3 socks
By the Pigeonhole Principle, if you pull 3 socks, you can have at most two different colors represented (e.g., 2 black and 1 white, or 2 white and 1 black). Therefore, at least two of the socks must be the same color, guaranteeing a matching pair.
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: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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