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A group consists of 4 girls and 7 boys. In how many ways can a team of 5 members be selected if the team has no girls

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Question

A group consists of 4 girls and 7 boys. In how many ways can a team of 5 members be selected if the team has no girls

Sum
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Solution

We have 4 girls and 7 boys and a team of 5 members is to be selected.

If no girl is selected, then all the 5 members are to be selected out of 7 boys

i.e. 7C5 = `(7!)/(5!2!)`

= `(7 xx 6.51)/(51 xx 2)`

= 21 ways

Hence the required number of ways are 21 ways.

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Chapter 7: Permutations and Combinations - Exercise [Page 124]

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NCERT Exemplar Mathematics Exemplar [English] Class 11
Chapter 7 Permutations and Combinations
Exercise | Q 25.(i) | Page 124

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