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L1 · Basic probability intuition
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Birthday Paradox
Birthday Paradox
Level 1
●●○○○
Easy
~5 min
Problem
In a room of 23 people, what is the probability that at least two share a birthday? Assume 365 equally likely birthdays and independence. Why is the answer surprisingly large?
Show a hint (2 available)
Show full solution
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Chevalier de Méré
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Exactly Two Heads in Three Flips
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