Problem of the Week

A new problem every Monday that challenges participants of all ages to think creatively and apply their math skills. Perfect for a weekly mental challenge.

Happy Birthday

Posted: April 13, 2026

61 % of users got this correct

Thirty-five students are chosen at random from a very large high school. What is the probability that at least two of the students have the same birthday. For this problem we will assume there are 366 different birthdays in a year. Be careful, the answer might surprise you!

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