Q.

The total number of ways in which 5 balls of different colours can be distributed among 3 persons so that each person gets at least one ball is             [2012]

1 75  
2 150  
3 210  
4 243  

Ans.

(2)

 Each person gets at least one ball.

3 persons can have 5 balls as follows.

Person No. of balls No. of balls
I 1 1
II 1 2
III 3 2

 

The number of ways to distribute balls 1,1,3 in first to three persons =C15×C14×C33

Also 3 persons having 1,1 and 3 balls can be arranged in 3!2! ways.

 Total number of ways to distribute 1,1,3 balls to the three persons =C15×C14×C33×3!2!=60

Similarly, total number of ways to distribute 1, 2, 2 balls to three persons =C15×C24×C22×3!2!=90

 The required number of ways =60+90=150