A student

A student is to answer 8 out of 10 questions on the exam.
a) find the number n of ways the student can choose 8 out of 10 questions
b) find n if the student must answer the first three questions
c) How many if he must answer at least 4 of the first 5 questions?


a =  45
b =  21
c =  35


Solution in text a =
Solution in text b =
Solution in text c =

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