In a school, the ratio of the number of girls to boys is 5:4. There are 120 boys,how many girls are in the school ?
If the ratio of girls to boys is 5:4, then for every 5 girls, there are 4 boys.
In this case, we have 120 boys, so we can set up the following proportion:
5 girls / 4 boys = x girls / 120 boys
Cross-multiplying, we get:
5 girls * 120 boys = 4 boys * x girls
600 girls = 4 boys * x girls
Dividing both sides by 4, we get:
600 girls / 4 = x girls
150 girls = x girls
Therefore, there are 150 girls in the school.