The ratio of girls to boys is 5 to 4 if there are a total of 27 students in the class how many are girls?

If the ratio is 5:4, and the number of pupils is 27, this means that there are 5 + 4 = 9 ninths to the whole. Therefore, 5/9 x 27 is equal to 15 and 4/9 x 27 is equal to 12. There are therefore 15 girls and 12 boys.