What is the percent difference between 420 and 840?
Using this tool you can find the percent difference between any two values. So, we think you reached us looking for answers to questions like: 1) What is the percentage difference between 420 and 840? 2) What is the absolute difference between 420 and 840? Or may be: What is the percent difference between 420 and 840?
See the solution to these problems just after the Percent Difference Calculator below.
How to work out percentage differences  Step by Step
To find the percent difference between two values x and y, use this formula:
% difference = 
x  y

Ã— 100%  
(x + y)/2

Where: x and y are two values of a give variable. Note that percent difference is not equivalent or equal to percent change. Percent change is used when comparing a new value to an old value where the old value is used as a reference. Percent difference is used just to compare two values without considering any order. It doesn't matter which of the two values is written first. That is why the absolute value^{(*)} is often used. Percent difference is also called relative percent difference.
(*) Note: absolute value means that we must consider always a positive value as for example: 1=1 (absolute value of 1 is 1) and 1= 1 (absolute value of minus 1 is also 1). See more about percent difference here.
Here are the solutions to the questions stated above:
1) What is the percentage difference between 420 and 840?
Use the above formula to find the percent difference between two numbers. So, replacing the given values, we have the percent difference equation
% Difference
= [(840  420) / (420 + 840)/2] x 100
= [(840  420) / (420 + 840) / 2] x 100
= [420 / 1260 / 2] x 100
= (420 / 630) x 100
= 66.666666666667
Where: y = 420 and x = 840, so y = 420 and x = 840
2) What is the absolute difference between 420 and 840?
This problem is not about percent difference, but about absolute difference:
The absolute difference of two real numbers x, y is given by x âˆ’ y, the absolute value of their difference. The minus sign denotes subtraction and z means absolute value. Absolute difference describes the distance between the points corresponding to x and y on the real line.
Now that you know what is absolute difference, The solution is very simple:
Percent Difference Calculator
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