What does it mean to say that you got an 80 percent on a 25-question test? Percentage is used to show how big one number is in relation to another. It does this by expressing the number as a fraction of 100. The steps below will help you convert whole numbers into percentages.

Decide what number you want to express as a percentage. For example, if you got 20 questions right on a 25-question test, you may find it helpful to know what percent you got right on the test. First, express the number you got right -- 20 -- as a percentage of the total number of questions, which was 25.

Write your numbers as a fraction. The number you want to convert to a percentage will be the numerator, which is the top number, and the other number will be the bottom number, referred to as the denominator. So, in the example, you would write the fraction as 20/25.

Divide the numerator by the denominator. In the example, if you divide 20 by 25, the answer is 0.8.

Multiply your result from Step 3 by 100. In the example, 0.8 x 100 = 80 percent.

Write your answer from Step 4 with a percent sign: 80%. So, you got 80 percent of the questions on your test correct.