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# Math: Basic Tutorials

## Simple Operations with Percent

Problems with percentages involve three parts: the percent, the total (base) number, and the part of that base number. This section explains how to work with these parts to solve simple operations with percent.

## Solving Simple Operations with Percent

Solving Simple Percent Word Problems Video transcript - RTF

## Examples & Activity

### Examples

Click on the titles below to view each example.

What number is 35 percent of 90?

Line 1: Translate the words into algebra. Let n equal the number we are trying to find, is represents the equals sign, 35 percent is 0 decimal 3 5, and of means multiply by 90. Therefore, the equation is n equals 0 decimal 3 5 times 90.

Line 2: Multiply 0 decimal 35 by 90 to solve for n, so the n equals 31 decimal 5.

Line 3: Therefore, 31 decimal 5 is 3 percent of 90.

36 is 75 percent of what number?

Line 1: Translate the words into algebra. Let b equal the number we are trying to find. Is represents the equals sign, 75 percent is 0 decimal 7 5, of means multiply by the number, b. Therefore, the equation is 36 equals 0 decimal 7 5 times b.

Line 2: Divide both sides of the equation to solve for b, so the equation is 36 divided by 0 decimal 7 5 equals 0 decimal 75 b divided by 0 decimal 7 5.

Line 3: Simplify to get 48 equals b.

Line 3: Therefore, 36 is 75 percent of 48.

What percent of 36 is 9?

Line 1: Translate the words into algebra. Let p equal the percent, of means multiply by 36, and is represents the equals sign. Therefore, the equation is p times 36 equals 9.

Line 2: Divide both sides by 36 to solve for p, so the equation is 36p divided by 36 equals 9 divided by 36.

Line 3: Simplify so that p equals 1 over 4.

Line 4: Convert the fraction to a decimal by dividing the numerator by the denominator so p equals 0 decimal 2 5.

Line 5: Convert the decimal to a percent by multiplying by 100 percent so p equals 25 percent.

Line 6: Therefore, 9 is 25 percent of 36.

### Activity

Try this activity to test your skills. If you have trouble, check out the information in the module for help.