Final answer:
The number of ways a student can select five questions from an exam containing nine questions is 126.
Step-by-step explanation:
The number of ways a student can select five questions from an exam containing nine questions is given by the combination formula:
C(n, r) = n! / (r!(n-r)!)
Substituting n = 9 and r = 5 into the formula:
C(9, 5) = 9! / (5!(9-5)!)
= 9! / (5!4!)
= (9 × 8 × 7 × 6 × 5!) / (5! × 4 × 3 × 2 × 1)
= (9 × 8 × 7 × 6) / (4 × 3 × 2 × 1)
= 126
Therefore, there are 126 ways a student can select five questions from a nine-question exam.