A man invites 4 men and 4 women to a party. In how many ways can they sit around a round table so that no two men are together?

A. 6
B. 24
C. 132
D. 144

Solution of the Mcq:

First, arrange the 4 men around the circular table in alternate chairs in (4 – 1)! = 3! ways. Now four alternate chairs are vacant. Each of the 4 women can now be seated in the vacant chairs in 4! ways. The total number of ways = 4! X 3! = 144 ways. Why the number of ways for men is 3! and not 4!? It is because it is immaterial where the first man is seated. The problem of uniqueness/permutation begins only after the first man is seated. Therefore, only three men have to be seated in some order now and they can be seated in the remaining 3 seats in 3! ways !!!

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