In a box of mixed socks, there are 10 red, 8 blue, and 6 green socks. What is the minimum number of socks you must pull out blindly to guarantee you have at least one matching pair of any color?
4 socks
By the Pigeonhole Principle, with 3 possible colors, pulling 4 socks guarantees that at least one color will appear twice.
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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