For this problem assume that there are 365 possible birthdays, and that each is equally likely.
a. What is the probability that there are two people in this room with the same birthday?
b. What is the smallest number of people that can be in a room so that the probability of two having the same birthday is greater than 50%?

Question

anonymous · Answer

my teacher did this once but I forgot

zarkon · Answer

Classic: http://en.wikipedia.org/wiki/Birthday_problem

anonymous · Answer

Hey, first off, thanks for the link. I got b), but I don't know how to do a). Can you help me out? Thanks.