Relative Error
Let the true value of a quantity be x and the measured or inferred value x_0. Then the relative error is defined by
where Deltax is the absolute error. The relative error of the quotient or product of a number of quantities is less than or equal to the sum of their relative errors. The percentage error is 100% times the relative error.
See also
Absolute Error, Error Propagation, Percentage ErrorExplore with Wolfram|Alpha
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References
Abramowitz, M. and Stegun, I. A. (Eds.). Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 9th printing. New York: Dover, p. 14, 1972.Referenced on Wolfram|Alpha
Relative ErrorCite this as:
Weisstein, Eric W. "Relative Error." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/RelativeError.html