There are 5 men and 5 ladies to dine at a round table. In how many ways can they sit so that no ladies are together?
Let first arranged 5 men in the round table by 4! (by using the formula (n-1)! Mention above)
Now there are 5 gaps created between 5 men (check the figure)
So we arrange 5 ladies in this gap by 5!
A total number of ways to arrange 5 men and 5 ladies is 5! × 4! = 2880