Q) How many groups can be made from 5 different green balls, 4 different blue balls and 3 different red balls, if at least 1 green ball and 1 blue ball are to be included?

A)

Choose 1 green ball and 1 blue ball, + extra balls [ 0 to 10 in number]

5C1 . 4C1 . (10C0 + 10C1 + 10C2 ....10C10)

= 5*4* (1+1)^10

= (20). 2^10 groups

________________________________________________________

## Saturday, December 13, 2008

Subscribe to:
Post Comments (Atom)

## No comments:

Post a Comment