SOLUTION: There are 600 pupils in a school. The ratio of boys to girls in this school is 3:5. How many girls and how many boys are in this school? Express how. Thanks.

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: There are 600 pupils in a school. The ratio of boys to girls in this school is 3:5. How many girls and how many boys are in this school? Express how. Thanks.      Log On


   



Question 547031: There are 600 pupils in a school. The ratio of boys to girls in this school is 3:5. How many girls and how many boys are in this school?
Express how. Thanks.

Answer by Maths68(1474) About Me  (Show Source):
You can put this solution on YOUR website!
Let
Boys = b
Girls = g
Given
Sum of the boys and girls
g+b=600.......(1)
Ratio of Boys to girls is 3:5
b:g=3:5
b/g=3/5
b=3g/5.........(2)
Put the value of b from (2) to (1)
g+b=600.......(1)
g+3g/5=600
Multiply by 5 both sides of the equation
5(g+3g/5)=5*600
5g+3g=3000
8g=3000
8g/8=3000/8
g=375
Put the value of g in (1)
g+b=600.......(1)
375+b=600
b=600-375
b=225


Boys = b = 225
Girls = g = 375