##### Basic Math & Pre-Algebra

Percents are commonly used in business to represent partial amounts of money. They're also used in statistics to indicate a portion of a data set. As you practice basic math problems, you'll discover that percents are closely related to decimals, which means that they're easier to work with than fractions.

• To change a percent to a decimal, move the decimal point two places to the left and drop the percent sign.

• To change a decimal to a percent, move the decimal point two places to the right and attach a percent sign.

• To change a percent to a fraction, drop the percent sign and put the number of the percent in the numerator of a fraction with a denominator of 100. If necessary, reduce the fraction.

• To change a fraction to a percent, first change the fraction to a decimal by dividing. Then change the decimal to a percent by moving the decimal point two places to the right and attaching a percent sign.

• Calculate simple percents by dividing. For example, to find 50% of a number, divide by 2; to find 25%, divide by 4; to find 20%, divide by 5; and so forth.

• You can calculate some percents by reversing the numbers. For example 14% of 50 is the same as 50% of 14, which equals 7.