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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 (i) no girl?
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Solution
A group consists of 4 girls and 7 boys. Out of them, 5 are to be selected to form a team.
(i) If the team has no girls, then the number of ways of selecting 5 members =\[{}^7 C_5 = \frac{7!}{5! 2!} = \frac{7 \times 6}{2} = 21\]
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