Converting between percentages and decimals

To change a percentage to a decimal, divide by 100.
Change 48% to a decimal: 48 ÷ 100 = 0.48

To change a decimal to a percentage, multiply by 100.
Change 0.67 to a percentage: 0.67 x 100 = 67%

Converting between percentages and fractions

Write the percentage as a fraction over 100 and then simplify:

Learn these equivalent fractions and percentages:

Percentage of a number

To find 20% of 30, convert the 20% to a decimal and then multiply by 30.
20% = 0.2
0.2 x 30 = 6
This is the best method as it always works.

Another way to find 20% of 30 is to first find 10% of 30 and then multiply by 2.
10% of 30 is 30 ÷ 10 = 3
2 x 3 = 6

Or a third way would be to recognize that 20% is equivalent to one fifth, and so just divide 30 by 5.
30 ÷ 5 = 6