Percentages can be a tricky concept to wrap your head around, but once you know a few simple tricks, they're easy to calculate. Here are four easy ways to calculate percentages. If you want to see more click here.
Calculating percentages using the percent button on a calculator
If you have a calculator that has a percent button, you can use that to calculate percentages. To do so, simply divide the number you want to calculate the percentage of by the percentage you want to calculate (in decimal form). Then, press the percent button. For example, if you want to calculate what 7.5% of 40 is, divide 40 by 0.075. Pressing the percent button will give you the answer: 300.
Calculating percentage increase or decrease
To calculate the percentage increase or decrease between two numbers, first figure out the difference (increase) between the two numbers you are comparing. You can do this by subtracting the smaller number from the larger number. Then, divide the increase by the original number and multiply the answer by 100. % increase = Increase ÷ Original Number × 100. To calculate a percentage decrease, simply reverse the direction of the division: % decrease = Decrease ÷ Original Number × 100.
For example, if you want to know what percent 2 is of 10, first you would subtract 2 from 10 to get 8. Then you would divide 8 by 10 to get 0.8. Multiply that answer by 100 to get 80%. (You can also multiply by a decimal equivalent of 100, like 1.0, 2.0, 5.0, and so on.)
What is 30 off of $40
Convert the percentage to a decimal. To do this, simply move the decimal point two places to the left. For example, 30% becomes 0.30.
Multiply the decimal by the whole number. In our example, you would multiply 0.30 by 40 to get 12.
To find the percentage of a specific number, simply multiply the decimal by the number. For example, to find 30% of 50, you would multiply 0.30 by 50 to get 15.
To calculate what percentage one number is of another, divide the first number by the second number and then convert to a percentage by moving the decimal point two places to the right. In our example, you would divide 12 by 40 to get 0.30. To convert this to a percentage, simply move the decimal point two places to the right to get 30%.
Calculating the original number when the percentage is known
To calculate the original number when the percentage is known, simply divide the percentage by 100 and then multiply the answer by the second number. For example, if you want to know what 20% of 300 is, divide 20 by 100 to get 0.2. Multiply that answer by 300 to get 60. (You can also multiply by a decimal equivalent of 100, like 1.0, 2.0, 5.0, and so on.)
Calculating the percentage when the original and final number are known
To calculate the percentage when the original and final number are known, simply divide the final number by the original number and then multiply the answer by 100. For example, if you want to know what percent 8 is of 40, divide 8 by 40 to get 0.2. Multiply that answer by 100 to get 20%. (You can also multiply by a decimal equivalent of 100, like 1.0, 2.0, 5.0, and so on.)"