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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 - Mathematics

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प्रश्न

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

योग
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उत्तर

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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अध्याय 7: Permutations and Combinations - Exercise [पृष्ठ १२४]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
अध्याय 7 Permutations and Combinations
Exercise | Q 25.(i) | पृष्ठ १२४

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