Math · 2
In the Birthday Paradox, how many people must be in a room for there to be roughly a 50% chance that two share a birthday?
Answer
23
Because each new person adds many new possible pairings, the number of shared-birthday chances grows much faster than intuition suggests, reaching 50% odds at just 23 people.
💡 Did you know?
Birthday Paradox reveals only 23 people needed in a room for 50% odds two share a birthday—our brains wildly underestimate how fast probabilities compound.
Other options people guess
- 50
- 100
- 183
Topics
- probability
- birthday-paradox
- statistics
- counterintuitive
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