There are 20 persons sitting in a circle. In that there are 18 men and 2 sisters. How many arrangements are possible in which the two sisters are always separated by a man?
Pick:
A) 18!x2  B) 17!  C) 17x2!  D) 12  E) 14
Now the first sister can sit in 20 ways and other sister can sit either left or right such that 2 ways .18!x2ll men can sit in remaning 18 seats i.e 18!   18!x2nswer is 18!x2   18!x2NSWER:18!x2
<result>A</result>
There are 20 persons sitting in a circle. In that there are 18 men and 2 sisters. How many arrangements are possible in which the two sisters are always separated by a man?