Question
In a group of 9 boys and 6 girls, 5 students have to be
selected. In how many ways it can be done so that only 2 boys are included.Solution
=> 9C2 × 6C3 = [9!/(9 -2)! 2!] × [6!/(6 -3)! 3!] => [9!/7! 2!] × [6!/3! 3!] => 720 ways
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