To take out or calculate a percentage, you generally follow this formula:
Percentage=(PartWhole)×100\text{Percentage}=\left(\frac{\text{Part}}{\text{Whole}}\right)\times 100Percentage=(WholePart)×100
Here’s how you do it step-by-step:
- Identify the part (the smaller value or portion you want to find the percentage of).
- Identify the whole (the total or maximum value).
- Divide the part by the whole to get a decimal.
- Multiply the decimal by 100 to convert it to a percentage.
Example
If you want to find what percentage 12 is of 60:
- Divide 12 by 60: 12÷60=0.2012÷60=0.2012÷60=0.20
- Multiply by 100: 0.20×100=20%0.20\times 100=20%0.20×100=20%
So, 12 is 20% of 60
Other related percentage calculations:
- To find a percentage of a number: Convert the percentage to a decimal (divide by 100) and multiply by the number.
Example: 10% of 150 is 0.10×150=150.10\times 150=150.10×150=15
- To find the whole from a part and percentage: Divide the part by the decimal form of the percentage.
Example: If 120 is 30%, the whole is 120÷0.30=400120÷0.30=400120÷0.30=400
- Using fractions: Convert the fraction to have a denominator of 100 or multiply by 100 to get the percentage.
Example: 425=16100=16%\frac{4}{25}=\frac{16}{100}=16%254=10016=16%
Mental math tip
You can use building blocks like 1%, 10%, and 50% to estimate percentages by adding or subtracting these parts
. This method works for most percentage calculations you’ll encounter.
