Consider a class of 5 girls and 6 boys. The number of different teams consisting of 2 girls and 3 boys that can be formed from this class, if there are two specific boys A and B, who refuse to be members of the same team, is:
Theorem of Combination -
Each of the different groups or selection which can be made by taking r things from n things is called a combination.
from the concept of combination.
Required np. of ways
=Total no. of ways - when A and B are always included.