Birthday Sharing
Probability
Level
2
How many people would you need in a room to guarantee that at least two persons would have the same birthday?
100
23
367
730
366
365
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1 solution
There are 365 days in a normal year but 366 in a leap year. So there are 366 possible birthdays. Therefore you need 367 people for it to be guaranteed that they share the same birthday.