Elementary Brain Teaser

Fun and accessible problems for younger students or beginners. Posted every Monday, these weekly brain teasers kickstart your week with a mental warm-up.

Student Card Game

Posted: March 2, 2026

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Two students are playing a game that consists of ten different numbered cards laying face down on a table. The faces of the cards are labeled using the numbers 1 – 10 (each card is numbered differently). If each student turns over a different card, what is the probability that the sum of the two cards is even?

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