A percentage is any number out of a 100. The symbol “%” is used to represent it in mathematics, instead of writing the number as a fraction with the denominator 100. Percentages help in calculating interest rates, allowance rises, pay raises, and sales or discounts. Percentages can be written as decimals as well. For example:

25% means 25/100

25/100 = 0.25

The same can be done when a decimal number has to be changed to a percentage. You multiply it with 100 to convert it to a percentage.

0.25 x 100 = 25% In order to do and solve percentages, there is a formula that is applied. This is simply by multiplying the fraction by 100 to give a result in percentage value. Whereas, a percentage value will be converted to a fraction or decimal value when 100 divides it. Here is an example.

• If 14 out of 30 people are men, what is the percentage of men?

14/30 x 100

=

46.6%

• If the price of a \$2.50 chocolate bar rises by 20%, what is the new price?

2.50 x 20/100 = 0.5

Now add this amount to the original price to find the price rise:

\$2.50 + \$0.5 = \$3.00  