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Question
Thank you for taking the time to answer my question. I believe it uses combinations and is a bit tricky:

The possibility that a basketball player will make a given free throw is 3/5. To find the probability that the player makes exactly 9 out of his next 10 free throws, evaluate the term 10 C 9 (3/5)^9(2/5)^1  in the expansion of (3/5 + 2/5)^10

If you could please include the way you got your answer as well, so I can help understand it for the future, it would be appreciated. Thank you again.

Answer
By 10 C 9, which is 10 choose 9, the answer is 10.

For (3/5)^9, it is known that 3^9 = 19,683 and and 5^9 = 1,953,125.
This would make the answer to dividing the 1st by the 2nd to be roughly 0.01.

It is also known that 2/5 = 0.4.

Thus, the entire answer is (10)(0.01)(0.4) = .04.

Looking at the exact answer in Excel, I get 0.040310784.

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