A sock drawer contains 10 loose black socks and 10 loose white socks in total darkness. What is the absolute fewest number of socks you must remove to guarantee a matching pair?
3 socks
By the Pigeonhole Principle, since there are only two color categories, drawing 3 socks guarantees at least two socks share the same color.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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