ACT Math · Probability and counting
In how many ways can a committee of 3 people be chosen from a group of 8 people?
In how many ways can a committee of 3 people be chosen from a group of 8 people?
Answer and explanation
Answer: G: 56
The order of selection does not matter for a committee, so use a combination: , choice G. Choice H () is the permutation , which counts each group times because it treats different orders of the same three people as different committees. Choice F () is , a product that does not model any selection. Choice J () is , which would count ordered choices with repetition allowed, impossible for a committee of distinct people.
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