There are18 boys and 20 girls in a class. What is the ratio of girls to boys?

20:18 = 10/9

To find the ratio of girls to boys in a class, we need to divide the number of girls by the number of boys. In this case, we have 20 girls and 18 boys.

So the ratio of girls to boys is 20/18.

To simplify this ratio, we can find the greatest common divisor (GCD) of 20 and 18, which is 2.

Dividing both 20 and 18 by 2, we get 10/9.

Therefore, the ratio of girls to boys is 10:9.