Four buses carry 148 students to an event The students are r

Four buses carry 148 students to an event. The students are randomly distributed among the vehicles with 40, 33, 25, and 50 students in each of the four buses. One of the students is then randomly selected. Let X denote the number of students on the bus which carries the previously selected student. One of the four bus drivers is also randomly selected. Let Y denote the number of students on her bus.

Calculate Var(X) and Var(Y)

Solution