**How to Calculate Percentages**

For calculating percentage problems there are many formulas we can use. The most basic one would look like: X/Y = P x 100. The formulas listed below are all mathematical variations of this formula.

The three basic percentage problems would look like this. X and Y are number, P is the percentage:

### a) Find P percent of X - Percentage Calculator 1

We will use the P% * X = Y formula here to find the percentage of a number. Let's calculate the 20% of 400:

• Let's convert the problem by using the percentage formula: P% * X = Y

• P is 20%, X is 400, so the equation is 20% * 400 = Y

• Convert 20% to a decimal by removing the percent sign and dividing by 100: 20/100 = 0.20

• Substitute 0.20 for 20% in the equation: 20% * 400= Y becomes 0.20 * 400 = Y

• Finally do the math: 0.20 * 400 = 80, Y = 80

• So 20% of 400 is 80

### b) Find what percent of X is Y - Percentage Calculator 2

Here we will use the percentage formula: Y/X = P% Let's see what percent of 40 is 6?

• Convert the problem to an equation using the formula: Y/X = P%

• X is 40, Y is 6, so the equation is 6/40 = P%

• Do the math: 6/40 = 0.15

• The result will always be in decimal form, not percentage form. You need to multiply the result by 100 to get the percentage.

• Converting 0.15 to a percent: 0.15 * 100 = 15%

• So 15% of 40 is 6.

### c) Find X if P percent of it is Y - Percentage Calculator 3

Let's use the percentage formula Y/P% = X to find out 10 is 20% of what?

• Convert the problem to an equation using the percentage formula: Y/P% = X

• Y is 10, P% is 20, so the equation is 10/20% = X

• Convert the percentage to a decimal by dividing by 100.

• Converting 20% to a decimal: 20/100 = 0.20

• Substitute 0.20 for 20% in the equation: 10/0.20 = X

• Do the math: 10/0.20 = X

• X = 50

• So 10 is 20% of 50

By purchasing products trough advertisements on the website, we might earn a small comission.