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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 at least three girls.
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उत्तर
We have 4 girls and 7 boys and a team of 5 members is to be selected.
When atleast 3 girls are included
Number of ways = 4C3 × 7C2 + 4C4 × 7C1
= `4 xx (7 xx 6)/(2 xx 1) + 1 xx 7`
= 84 + 7
= 91 ways
Hence the required number of ways are 91 ways.
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