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Probability puzzles require you to weigh all the possibilities and pick the most likely outcome.


Puzzle ID:#4631
Fun:*** (2.43)
Difficulty:*** (2.69)
Submitted By:Dazza**
Corrected By:twixy




How many people do you need to enter a room before the probability of any 2 or more people sharing a birthday (day and month only, not year) is greater than 50%?

Assume for the sake of the puzzle that birthdays in the population at large are equally spread over a 365 day year.


It is easier to calculate the probability that all birthdays in the group are unique.

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