Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. Math explained in easy language, plus puzzles, games, quizzes, worksheets and a forum. For K-12 kids, teachers and parents. The word ‘percentage’ is derived from a Latin word ‘per centum’, which means by 100.The standard symbol used to represent percent or percentage is ‘%’, which evolved by the gradual contraction of the Italian word ‘per-cento’, which means ‘for a hundred’. Percent error formula is used to find how much error is there in terms of percentage. Click now to know how to calculate percent error using percentage error formula. Percent error is the difference between an approximate or measured value and an exact or known value. Here is how to calculate percent error. jessica bedford September 23, 2017 at 3:20 pm. okay say you have two different percent errors, because of a word problem were there the end result id two groups of percent errors, how do you know which one is the accurate one. Science Trends is a popular source of science news and education around the world. We cover everything from solar power cell technology to climate change to cancer research. So Rømer was quite a bit off by our standards today, but considering he came up with this estimate at a time when a majority of respected astronomers, like Cassini, still believed that the speed of light was infinite, his conclusion was an outstanding contribution to the field of astronomy. Guide to Percent Error Formula. Here we learn how to calculate Percent Error using its formula with practical examples and downloadable excel template.