Question

If the percent difference between two measured values, $4.6cm$ and $5.0cm$ is $n$%. Find $n$ ? (Round off to the closest integer)

Answer 1

Sometimes it is instructed to compare the results of two measurements when there is no known or accepted value. The comparison is expressed as a percent difference, which is the ratio of the absolute difference between the experimental values $E_1$ and $E_2$ to the average or mean value of the two results, expressed as a percent.
Percent difference $=\left(\frac{\text{Absolute difference}}{\text{Average}}\right)\times 100\%$
$=\frac{|E_2-E_1|}{|E_2+E_1|/2}\times 100\%$
$=\frac{|5.0-4.6|}{|5.0+4.6|/2}\times 100\%$
$=\frac{0.4}{4.8}\times 100\%$
$=8\%$