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?

Answer

`12!xx2`

Explanation

Let the secretary A sit on one side of chairman B and deputy secretary C sit on other side of chairman. Then we have to arrange 12 persons and one grup ABC in a circle.
So, total number of arrangements `=2xx12!`