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?
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