Problema Solution

The ratio of girls to boys is 3:5. If there were 120 children altogether how many girls are there?

Answer provided by our tutors

Let

x = the number of girls

y = the number of boys

x : y = 3 : 5 cross-multiply

5x = 3y

There are 120 children altogether:

x + y = 120

We need to solve the following system of equations:

5x = 3y

x + y = 120

........

click here to see the system of equations solved for x and y

........

x = 45 girls

y = 75 boys

There are 45 girls.