A committee of 10 members sits around a table. But, President and Vice-president sit together. Let us consider President and Vice-president as one unit. They can be arranged among themselves in 2! ways. Now, this unit with the other 8 members of the committee is to be arranged around a table, which can be done in (9 – 1)! = 8! ways.
∴ Required number of arrangements = 8! × 2! = 2 × 8!
