Question

The number of boys and girls are 7:5,boys are 8more than girls, find strength

Answer 1

Let Boys = b Girls = g The number of boys and girls in a class are in the ratio 7:5 b:g=7:5 b/g=7/5 b5=g7 b5/5=g7/5 b=g7/5...............(1) the number of boys is 8 more than the number of girls b=g+8.............(2) Put the value of b from (1) to (2) g7/5=g+8 5*(g7/5)=5*(g+8) g7=5g+40 g7-g5=40 2g=40 2g/2=40/2 g=20 Put the value of g in (2) b=20+8 b=28 Boys are 28 and Girls are 20

Answer 2

let boys be 7x
let girls be 5x
7x=5x+8
7x-5x=8
2x=8
x=8/2
x=4
No.of boys=7x=7*4=28
No.of girls=5x=5*4=20
Therefore, total strength=28+20=48