Question

Average weight of all students is 60kg ina class .Aveeage weight of boys is 70kg and that of firl 55kg .If total weight of boys and girls is 9000kg .Calculate no.of boys and girls

Answer 1

Answer:

no. of boys=50

no. of girls=100

Step-by-step explanation:

total no. of students= total wt./average wt.

= 9000/60

= 150

let no. of boys be x

therefore, no. of girls=150-x

total wt. of, boys= 70x

girls= 55(150-x)

A.T.P.

70x + 55(150-x) = 9000

70x + 8250 - 55x = 9000

70x - 55x = 9000-8250

15x = 750

x=50

hence, 150-x=150-50=100