SOLUTION: a candidate is expected to attempt 12 out of 15 questions in a test. in how many ways can this be done if the first 8 questions are compulsory

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Question 964119: a candidate is expected to attempt 12 out of 15 questions in a test. in how many ways can this be done if the first 8 questions are compulsory
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
a candidate is expected to attempt 12 out of 15 questions in a test.
in how many ways can this be done if the first 8 questions are compulsory
He chooses the first 8 questions in 1 way, since they are compulsory.
That leaves 15-8=7 questions of which he must choose 12-8=4.

That's 7 choose 4 or 7C4 or 35 ways. 

Edwin