SOLUTION: In a group of 8 people, what is the probability that at least 2 persons have the same birthday. (the same month and day, excluding February 29)

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Question 1129119: In a group of 8 people, what is the probability that at least 2 persons have the same birthday. (the same month and day, excluding February 29)
Answer by ikleyn(52781)   (Show Source): You can put this solution on YOUR website!
.
The complement event is that in a group of 8 people all have different birthdays,

and the probability of this complement event is 


    P' =  =  = 0.925665 (approximately).


Then the probability of the event under the question is the complement to it


    P = 1 - P' = 1 - 0.925665 = 0.074335 = 7.4335%.       ANSWER

Solved.


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