Relative ErrorsDate: 08/03/97 at 14:09:18 From: Max Wasserman Subject: Relative errors How do you find the relative error of a measurement? Date: 08/04/97 at 08:53:32 From: Doctor Jerry Subject: Re: Relative errors Hi Max, Suppose you are measuring someone's height. If her actual, true height is 60 inches and you measure 61 inches, then the absolute error of measurement is 61-60 = 1 inch. The percentage error is [(61-60)/60]*100 = [1/60]*100 = 5/3, which is a little less than a 1 percent error. The relative error is just (61-60)/60 = 1/60. The idea is that if you make an error of 1 inch in measuring a person's height, this is a relatively large error compared to making an error of 1 inch in measuring the length of a one-mile racetrack. The absolute errors would be the same, but the relative errors would be 1/60 and [(5280*12+1)-5280*12]/(5280*12)=1/(5280*12), which is quite a bit smaller than 1/60. -Doctor Jerry, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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