Every number has a percentage. Percentage means "per or out of 100\" For example, if there is 10 pieces of candy in a bowl and you take all the pieces, you have 100% of the candy. If you only take 5, half of the candy, you have 50%. Understanding that percentages are everywhere is a good first step to learning to use them in math. When would this type of math come in handy? One really common example is when a store has a sale. The store usually offer a percentage off the price. This is the perfect example of when you might get to practice subtracting percentages off a number. The easiest way to deal with percentage is by converting them to decimals so they interact easily with the other numbers in the math problem.
Convert the percentage to a decimal. To do this, remove the percentage sign. This is a whole number with a decimal at the end. Move the decimal to the left 2 places. If the percentage only has one number, add a 0 to the left of the number. If the percentage is over 100% there will be a number in front of the decimal.
Multiply the number by the newly converted percentage.
This number is the difference between the first number and the per cent. A common application is to find the cost of a product. In this case, you will take the difference and subtract it from the first number.
Before doing the math with a calculator, make sure your teacher allows them. If you have to show your work, work the problem out on paper first and use the calculator to check your math.
Tips and warnings
- Before doing the math with a calculator, make sure your teacher allows them. If you have to show your work, work the problem out on paper first and use the calculator to check your math.