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Math

Some of the content of this guide was modeled after a guide originally created by the Openstax and has been adapted for the GPRC Learning Commons in September 2020. This work is licensed under a Creative Commons BY 4.0 International License .

Calculating Percentages

Check out this presentation by our Math Tutor Dr. Shohreh Rahmati about how to calculate percentages.

In order to find a percentage of a number, we do the following steps:

Step (1) Write the question as a fraction

Example (1): 18 is what percent of 21?

Step (1) The question in fraction form is: 18/21

Step (2) Multiply Step (1) by 100: 18/21×100=85.71%

Example (2): 16 is what percent of 45?

Step (1) Write the question as a fraction: 16/45

Step (2) Multiply Step (1) by 100: 16/45  ×100=35.55%