Number of ways to choose 3 students from a class of 10:
A30
B120 (= 10!/(7!×3!))
C720
D1000
Answer & Solution
Correct answer: B. 120 (= 10!/(7!×3!))
Combinations C(10, 3) = 10! / (7! × 3!) = (10 × 9 × 8)/(3 × 2 × 1) = 120.
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