Two representatives are chosen at random from a group of 100 students that has 50 girls and 50 boys. What is the probability that the representatives seledted are either both boys or both girls?

Answer 1

numbers of groups of twos from 50 = C(50,2) = 1225
number of possible groups of twos from 100 = 4950

prob = 2(1225)/4950 = 49/99