Question
A group consists of 11 boys and 9 girls. In how many
ways can 7 boys and 5 girls be selected from the group?Solution
Required number of ways = 11 C 7 × 9 C 5
= (11! / (7! × 4!)) × (9! / (5! × 4!))
= 330 × 126 = 41,580
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