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Mathematics

The Birthday Problem and Its Probability Surprises

Quick fact

With just 23 people, the probability that at least two share a birthday is about 50.7%. With 50 people, it jumps to about 97%.

Why this is interesting

You walk into a room with 22 strangers. Would you bet that at least two of you share the same birthday? Most people would guess no, but the odds say it's more likely than not.