In how many ways can a committee of 4 be chosen from 9 students?
Answer and explanation
Correct answer: D. 126
- Step 1: The order does not matter, so use combinations: 9C4 = 9! / (4! x 5!). Step 2. = 126. Answer: 126. Why not the others: 3024: That counts ordered selections. 36: That multiplies the two numbers. 252: That doubles the correct value.
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