How many distinct 4-person committees can be formed from a group of 9 eligible candidates?
Answer and explanation
Correct answer: D. 126
- Step 1: Order does not matter, so use combinations: C(9, 4). Step 2. Formula: 9! / (4! (9 - 4)!) = 9! / (4! 5!). Step 3. Compute: (9 8 7 6) / (4 3 2 1) = 3024 / 24 = 126. Answer: 126. Why not the others: 3024 is permutations P(9, 4) where order matters; 36 multiplies 9 by 4; 72 divides 3024 by 42.
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