# Add or Subtract a Percentage

We think you've reached us looking for answers like: How to increase 10 percent to 100? Or may be: Add or Subtract a Percentage Calculator. See the solutions to these problems below.

## How to add a percentage to a number - Step by Step

To add a percentage (%) to a number, i.e., If you want to add a y percent to an x amount, you can use the following formula:

End Value = x + ((^{y}/

_{100}) * x )

Where: x represents the start or inicial value and y the percent we want to add. See the example below:

### How to increase or add 10% to 100?

Plugging the values in the formula above:

End Value = 100 + (( ^{10} / _{100} ) x 100)

End Value = 100 + (( 0.1 ) x 100 )

End Value = 100 + ( 10 )

End Value = 110 (Answer).

## How to subtract a percentage from a number - Step by Step

To subtract a percentage (%) from a number, i.e., If you want to subtract a y percent to an x amount, you can use the following formula:

End Value = x - ((^{y}/

_{100}) * x )

Where: x represents the start or inicial value and y the percent we want to subtract. See the example below:

### How to decreasee or subtract 10% to 100?

Plugging the values in the formula above:

End Value = 100 - (( ^{10} / _{100} ) x 100 )

End Value = 100 - (( 0.1 ) x 100 )

End Value = 100 - ( 10 )

End Value = 90 (Answer).

To find more examples, just choose one at the bottom of this page.