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Question
It is required to seat 5 men and 4 women in a row so that the women occupy the even places. How many such arrangements are possible?
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Solution
Arrangement of 4 women sitting at 4 even places = 4! = 24
Ways to seat 5 men at 5 odd places = 5! = 120
Arrangement of 4 women to sit at even places and 5 men to sit at odd places
= 4! x 5!
= 24 x 120
= 2880
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