Question
In a group of 8 boys and 5 girls, 5 students have to be
selected. In how many ways it can be done so that only 2 boys are included.Solution
=> 8C2 × 5C3 = [8!/(8 -2)! 2!] × [5!/(5 -3)! 3!] => [8!/6! 2!] × [5!/2! 3!] => 280 ways
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