a Find the number of ways in which 5 persons can sit in a ro

(a) Find the number of ways in which 5 persons can sit in a row.

(b) How many ways are there if 2 of the persons insist on sitting next to one another?

(c) Solve part (a) assuming they sit around a circular table.

(d) Solve part (b) assuming they sit around a circular table.

Solution

a)5 person can sit in a row in 5! ways

b)The answer is 4! x 2! = 4x3x2x1x2x1 = 48

3)around the circular table person can sit in 1/2*(5-1)! ways =12

4)when two person sit together

   1/2*3! =3