A basket contains 10 red apples and 10 green apples. You are blindfolded and reach into the basket. What is the minimum number of apples you must pull out to guarantee you have at least one matching pair of the same color?
3 apples
By the Pigeonhole Principle, if you draw 3 apples with only 2 possible colors (red and green), you must have at least two of the same color.
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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