Q.

How many different nine digit numbers can be formed from the number 223355888 by rearranging its digits so that the odd digits occupy even positions            [2000]

1 16  
2 36  
3 60  
4 180  

Ans.

(3)

X-X-X-X-X. The four digits 3,3,5,5 can be arranged at (-) places in

4!2!2!=6 ways

The five digits 2,2,8,8,8 can be arranged at (X) places in

5!3!2!=10 ways

 Total number of arrangements=6×10=60 ways