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Figure This!

 

With 30 strangers in a room, the probability of having at least two matching birthdays is about 71%.

The probability that two people were born on the same day is different from the probability that two people were born on a given day.

How many US presidents have had the same birthday? How many of them died on the same day?

Think of an event that has a 100% probability of occurring.

 


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