A box holds four cards numbered 1, 2, 3, and 4. You draw two cards at random. The sum of the numbers on the two cards is an even number. If one of the cards you drew is the number 3, what is the other card?
1
For the sum of two numbers to be even, both numbers must be even or both must be odd. Since 3 is odd, the other card must also be odd. The only other odd card in the set {1, 2, 3, 4} is 1.
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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