Official solution
6 men can sit at the round table = \[\left( {6 - 1} \right)! = 5!\] ways
Now at the round table among 6 men there are 6 empty places and 5 women can sit at those 6 empty positions.
So total no of ways 6 men and 5 women can dine at the round table
= \[5!\, \times {}^6{C_5} \times 5!\]
= \[5!\, \times 6 \times 5!\]
= \[5!\, \times 6!\]