How to Calculate Percentage

When trying to calculate a percentage, think of the percent as part/whole. For example, if you were asked to calculate 35% of 40, you would write 35/40, which would result in 0.875. Moving the decimal two places to the right will result in your answer (87.5%).

Calculation of a Percentage

Calculation of Percentage

Sometimes instead of being given a percent, you’re asked to find the percentage. Here we have two problems we’re going to do where we have to find the percentage. The first one says what percent, so again we don’t know the percent, of 40 is 35?

In this case we can think of a percent as a part divided by a whole. In this case our part would be that 35 out of the whole which would be 40. Then we divide our numerator by our denominator to get our decimal 35 divided by 40 is 875 thousandths, and then we convert our decimal to a percentage by either multiplying times 100 or moving our decimal two places to the right.

That’s 87 and 5/10 percent. 35 is 87 and 5/10 percent of 40. The other way to do it is to, again, start by setting up your thinking of your percentage as a part out of a whole so setting up your fraction.

This case when we did when we do what percent of 25 is 12, our part is 12 and our whole is 25. Remember, a percent is a part out of 100. If we convert our denominator to something over 100 then we’ll know what that part is.

To change our denominator from 25 to 100, we have to multiply times 4 which means we have to do the same to our numerators, so 12 times 4 is 48, so that’s 48 out of 100 or 48 percent. 12 is 48 percent of 25. It’s not quite half of it, it’s not quite 50 percent, it’s 48 percent.



by Mometrix Test Preparation | Last Updated: June 3, 2020