Mr minus picks 2 students at random from his class of 31 students.15 of his students are boys. What is the probability he picks 2 girls from the class?
Many thanks.
so there are 15 boys and 16 girls
prob(that both picked are girls)
= C(16,2) / C(31,2) = 120/465 = 8/31
or
prob(girl, girl)
= (16/31)(15/30)
= (16/31)(1/2) = 8/31