There are 25% more boys than girls in a school. If there are 180 pupils altogether, how many boys are there?

Question

There are 25% more boys than girls in a school. If there are 180 pupils altogether, how many boys are there?

Answer 1

Let x = the number of boys and y = the number of girls:

• There are 25% more boys than girls in a school:  x = 1.25y
• there are 180 pupils altogether: x + y = 180

 

Since x = 1.25y, let's substitute 1.25y in place of x in the second equation and solve for y:

 

x + y = 180

1.25y + y = 180

2.25y = 180

 

Solve for y.  Once you have y, x = 1.25 y.  Check your answer by making sure that x+y add up to 180.