In how many ways can a committee of 3 be chosen from 9 people?
Answer and explanation
Correct answer: C. 84
- Step 1: Order does not matter, so use combinations: C(9, 3) = 9! / (3! x 6!).
- Step 2: C(9, 3) = 84.
Answer
84.
Why not the others: '504' counts ordered selections (permutations) instead of combinations; '27' multiplies n and k; '93' adds n to the correct count.
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