Let's start by recalling that the percent proportion is a proportion that sets the ratio of a part of a whole equal to the ratio of a percent out of 100.
part/whole=percent/100
We want to find what percent of 60 is 15. Let n represent the percent.
15/60=n/100
Now we can solve the proportion we got for n. Let's do this by using the fact that the cross products of any proportion are equal.
