Question

The ratio of girls to students at a middle school is 10 to 18. If there are 270 students at the school, how many are girls?

Answer 1

10/18 = 0.5555 = 55.6%

0.556  ×  270 = 150

You are Correct! 

Answer 2

A good way of doing this problem would be to use cross multiplication of ratios
<u />$\frac{10 girls}{18 students} = \frac{X girls}{270 students}$

Then cross multiply

(10 girls)(270 students)=(X girls)(18 students)

2700=18x
150=x