Counting and complements · Office party · difficulty 1 of 5

Someone shares your birthday

You walk into a party with 23 other people. Assume everyone's birthday, yours included, is independent and uniform over 365 days (ignore leap years). What is the probability that at least one of the other 23 people has the same birthday as you?

Answer with a probability. First lock in a gut guess with an 80% range, then solve it properly, then watch a simulation settle on the truth.

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