A group of 7 members having a majority of boys is to be formed out of 6 boys and 4 girls. The number of…
A seven-member majority of boys allows 4 boys/3 girls, 5 boys/2 girls or 6 boys/1 girl. Count = C(6,4)C(4,3)+C(6,5)C(4,2)+C(6,6)C(4,1) =15×4+6×6+1×4=100. Thus “100”; “80”,…
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A group of 7 members having a majority of boys is to be formed out of 6 boys and 4 girls. The number of ways the group can be formed is
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Correct answer B
A seven-member majority of boys allows 4 boys/3 girls, 5 boys/2 girls or 6 boys/1 girl. Count = C(6,4)C(4,3)+C(6,5)C(4,2)+C(6,6)C(4,1) =15×4+6×6+1×4=100. Thus “100”; “80”, “90” and “110” do not equal the sum. Member order is irrelevant.
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