The mean weight of 150 students in a class is 60 Kg. The mean weight of Boy students is 70 Kg and that of a girl students is 55 kg. Find the number of Boys and Girls in the class.
A)50 and 100
B)100 and 50
C)150 and 200
D)200 and 150

Question

Quizplus · Accepted Answer

The total weight of all students is 150 * 60 = 9000 Kg. Let the number of boys be x and the number of girls be 150 - x. The total weight of boys is 70x and of girls is 55(150 - x). Setting up the equation: 70x + 55(150 - x) = 9000. Solving for x gives x = 50 (boys) and 150 - x = 100 (girls).

The Mean Weight of 150 Students in a Class Is