SOLUTION: how many ways can 9 cd's be selected from a stack of 15 different cd's?

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Question 562493: how many ways can 9 cd's be selected from a stack of 15 different cd's?
Answer by issacodegard(60) About Me  (Show Source):
You can put this solution on YOUR website!
Hi, we don't care about the order of the cd's we choose, and we don't consider repetition (since the cd's are different). So, this is basically the number of 9 element subsets taken from a 15 element set.
This is computed as 15C9, which equals,
15%21%2F%289%21%2815-9%29%21%29=5005