If you were to pick two students out of a class of 7 girls and 6 boys, what is the probability that the students chosen are two boys?
The number of ways to choose 0 girls from a group of 7 girls is: 7C0
The number of ways to choose 2 boys from a group of 6 boys is: 6C2
The number of ways to choose 2 students from a group of 13 students is: 13C2
So, the probability is: 7C0 x 6C2 / 13C2