Question

the number of ways in which 7 boys sit in a round table so that two particular boys may sit together is

Answer 1

2×5! = 240 ways may be the your answer

Answer 2

• Number of ways in which n people can sit in a round table=(n-1)!
• So to make them sit together, consider them as a single unit in the sitting arrangement i.e. n=6.
• Number of ways so that two particular boys may sit together in the round table=

(6-1)!*2(The two particular boys can also be switched among themselves)

=120*2

=240