percentage
percentage errors

Percentage errors are a way to measure how accurate or inaccurate a calculation or measurement is. It tells us how far off our answer is from the correct one, in terms of a percentage.

Simple Illustration

Imagine you have a big jar of candies and you want to count how many candies are inside. You count and get 50 candies, but later you find out there are actually 55 candies in the jar. The percentage error in your count would be how much you were off (5 candies) compared to the correct amount (55 candies), expressed as a percentage.

Worked Example

Let’s calculate the percentage error in this example:

Actual number of candies = 55
Your count = 50

Error = Actual number – Your count
Error = 55 – 50
Error = 5

Percentage error = (Error / Actual number) x 100
Percentage error = (5 / 55) x 100
Percentage error = 0.0909 x 100
Percentage error = 9.09%

So in this case, your count was off by 9.09% from the actual number of candies in the jar.