A club has 10 members. In how many ways can a committee of 2 be chosen?
Answer and explanation
Correct answer: A. 45
- Step 1: Order does not matter, so use combinations.
- Step 2: C(10,2) = 10! / (2! x 8!) = 45.
Answer
45.
Why not the others: 90 counts ordered selections; 20 simply multiplies n by k.
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