In how many ways can a committee of 3 students be selected from a class of 8 students?
Answer and explanation
Correct answer: C. 56
- Step 1: Order does not matter in committee selection, so use combinations: C(n, r) = n! / [r!(n - r)!].
- Step 2: Substitute n = 8, r = 3: C(8, 3) = (8 7 6) / (3 2 1).
- Step 3: Simplify: (8 7 6) / 6 = 56.
Answer
56.
Why not the others: '336' calculates permutations P(8, 3) = 8 7 6, treating order as significant; '24' multiplies 8 by 3; '120' calculates C(10, 3).
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