A round table conference is to be held between delegates of 20 countries. In how many ways can they be seated if two particular delegates are
never together?

A round table conference is to be held between 20 delegates of 20 countries. In how many ways can they be seated if two particular delegates are always together.

A round-table conference is to be held among 20 delegates belonging from 20 different countries. In how many ways can they be seated if two particular delegates are (i) always to sit together, (ii) never to sit together .

A round-table conference is to be held among 20 delegates belonging from 20 different countries. In how many ways can they be seated if two particular delegates are (i) always to sit together, (ii) never to sit together .

A round table coference is to be held between 20 delegates. How many seating arrangements are possible if two particular delegates are always to sit together .

In how many ways can 6 persons be seated at a round table?

In how many ways can 5 persons be seated at a round table?

In how many ways can 8 boys be seated at a round table?

In how many ways can 3 people be seated in a row containing 7 seats?

There are 5 boys and 3 girls. In how many ways can they be seated in a row so that al the three girls do not sit together

In how many ways can 20 persons be seated round a table if there are 9 chairs.