Question
From a group of 10 men and 7 women, in how many ways can
8 men and 4 women be selected?Solution
Selection method of 4 women out of 7 women = 7C4 =7 ! / (7-4)! ×4! =7! /3! ×4! =7×6×5×4!)/3! ×4! =7×6×5)/3×2 =35 Method of selecting 8 out of 10 men = 10C8 10 ! / (10-8)! ×8! = (10×9×8!) / (2!) ×8! =45  Total method of selection = 35×45= 1575.
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