In how many ways can a committee of 2 be chosen from 7 people?
Answer and explanation
Correct answer: D. 21
- Step 1: Order does not matter, so use combinations: C(7, 2) = 7! / (2! x 5!).
- Step 2: C(7, 2) = 21.
Answer
21.
Why not the others: '42' counts ordered selections (permutations) instead of combinations; '14' multiplies n and k; '28' adds n to the correct count.
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