Question

Answer this question with proper solution.

Answer 1

let number of boys = x
so number of girls = 180-x
total weight = 180*50
weight of all boys = 60x
weight of girls = 45*(180-x)

total weight = weight of boys + weight of girls

180*50= 60x + 45*(180-x)
9000 = 60x + 8100 - 45x
9000-8100 = 15x
900 = 15x
no of boys = x = 60
number of girls =180-x = 120 

Answer 2

let the number of boys=x
number of girls=180-x
total students weight =180*50
boys weight=60x
girls weight=(180-x)45
total weight =boys weight+girls weight
180*50=60x+(180-x)45
9000=60x+8100-45x
900=15x
x=60=number of boys
number of girls=120