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Adding Percentage Formula: = "Number to find % of" x (1+(%))

Adding percentages onto a starting number is an important mathematical operation that can be difficult to perform by hand. This sort of calculation is important in a wide variety of fields, including construction, graphic design, architecture and computer programming, and is likely to occur in math homework as well.
Our Adding Percentage Calculator can help you find out exactly how much larger a particular number would be when increased by a given percent. Simply follow the instructions below to determine your result.

List of Values
There are three values at work in this calculation:
• Base number
• Percentage
• Result

The first two must be provided by you and entered into the appropriate fields, while the third value will be determined by the online calculator.

How to Use the Calculator
Enter the base number into the first text field, found just to the left of the words “Number to Find % Of.” This is the number to which you will be adding the percentage. Enter your percentage into the second field, located just below the first and positioned to the left of the words “% (I.E .09).”
Click the large button labeled “Calculate!” to generate the result, displayed just beneath the lower advertisement. The result will be expressed as “Original Value + Percentage Increase: [your value]” for easy interpretation.

Inputting Percentages
Please note that the percentage must be entered as expressed in relation to the number 1. That is to say, 50% can be entered as:
• 0.5
• .5
• .5000
• .50

or any other equivalent value, but not as 50 — the number 50, when entered into the Percentage field, would be interpreted as meaning 5000%. Negative percentages are also possible, as is subtraction. Simply place a minus sign in front of the percentage to subtract that percentage from the first number, rather than adding to it.
For example, to subtract 30% from 350, enter the number 350 into the first field and -0.3 into the second one to find the result (245, in this case).

The Math Under the Hood
Our calculator performs its operations with lightening speed, and the actual calculation looks very simple when reduced algebraically: x(1+%), where “x” is your starting number and “%” is the percentage. Since the percentage is expressed in hundredths — as a number less than one, with up to two decimal places — adding the percentage to a base number of 1 results in the amount by which your primary number must be multiplied.
Described another way, it is the number of times your starting value must be added to itself. If your percentage is less than 100%, this number will be between 1 and 2, though the number may be greater for larger percentages.