In how many ways 10 passengers can board three buses if no bus remains empty?

Five balls are to be placed in three boxes in how many diff.ways can be placed the balls so that no box remains empty if (i) balls and boxes are diff,(ii) balls identical and boxes diff.(iii) balls diff and boxes identical (iv) balls as well as boxes are identical

Five balls of different color are to be placed in three boxes of different size. Each box can hold all five. In how many different ways can we placed the balls so that no box remains empty?

Five balls of different colours are to be placed in three boxes of different sizes.Each box can hold all five.In how many different ways can we place the balls so that no box remains empty?

In how many ways 10 persons can be divided into 5 pairs?

In how many ways 7 books can be arranged from 10 books?

In how many ways can 4 women draw water from 4 taps, if no tap remains unused?

In how many ways can 6 women draw water from 6 wells, if no well remains unused?