Question

In how many ways can 15 members of a council sit along a circular table, when the Secretary is to sit on one side of the Chairman and the Deputy Secretary on the other side.

• A. $2 \times 12!$
• B. 24
• C. $2 \times 15!$
• D. None of these

Answer 1

Answer: (A)

$2 \times 12!$

Answer 2

Since total members are 15, but one is to left, because of circular condition, therefore remaining members are 14 but three special member constitute a member. Therefore required number of arrangements are $12\mspace{6mu}!\mspace{6mu} \times 2$, because, chairman remains between the two specified persons and the person can sit in two ways.