#### Answer

20

#### Work Step by Step

To find this, you need to set up an equation. To do this, you need to convert the percent to a decimal. So divide 75 by 100 to get .75. Now, you can set up the equation, which is n x .75=15. Now that you have the equation, you can find the answer. To do this, you have to solve for n. So divide both sides by .75, and you will get n=20.