Counting
| ResidentBiscuit (2650) |  |
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4 men, 6 women, 3 spots to fill. A) One man and two women B) At least two men C) At least one person of each sex I can't get these, and I don't know why. My logic seems right, but it doesn't get the right answer. A) Pick a man, 4 choices. Pick a woman, 6 choices, pick the other woman, 5 choices. 4 * 6 * 5 outcomes. This is wrong. B) Pick a man, 4 choices. Pick another man, 3 choices. Pick the last person, 6 + 2 choices. 4 * 3 * 8 outcomes. Wrong. C) Pick a male, 4 choices, pick a female 6 choices, pick the last, 5 + 3 choices. 4 * 6 * 8 outcomes. This is also wrong. The hell is going wrong here? Have a final for this tomorrow and figured I'd brush up on my counting and I guess I just completely forgot how to do anything of this. | |
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| cire (2354) | |
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You're using the formula for permutations. You should be using the formula for combinations. A) (4!/(1!*(4-1!))) * (6!/(2!*(6-2)!) = 4 * (6*5 / 2 ) = 4*15 = 60 | |
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| ResidentBiscuit (2650) | |
| Oh wow I don't know how I overlooked that. Figures it was just some simple issue. Thanks though | |
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