InterviewSolution
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InterviewSolution
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From A Group Of 7 Men And 6 Women, Five Persons Are To Be Selected To Form A Committee So That At Least 3 Men Are There On The Committee. In How Many Ways Can It Be Done? |
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Answer» We may have (3 men and 2 women) or (4 men and 1 woman) or (5 men only). Required number of WAYS = (7C3 * 6C2)+(7C4 * 6C1)+(7C5) =>[(7*6*5)/(3*2*1) * (6*5)/(2*1)]+(7C3 * 6C1) + (7C2) => 525 + [(7*6*5)/(3*2*1)* 6]+[(7*6)/(2*1)] = (525 + 210 + 21) = 756. We may have (3 men and 2 women) or (4 men and 1 woman) or (5 men only). Required number of ways = (7C3 * 6C2)+(7C4 * 6C1)+(7C5) =>[(7*6*5)/(3*2*1) * (6*5)/(2*1)]+(7C3 * 6C1) + (7C2) => 525 + [(7*6*5)/(3*2*1)* 6]+[(7*6)/(2*1)] = (525 + 210 + 21) = 756. |
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