Martha estimated there were 95 marbles in a jar for a contest. The actual number of marbles in the jar was 117. What was the percent error of Martha's estimation?
It is 18.80%. You use the percent error formula: %error= (true value-estimated value)/true value. So (117-95)/117 = .188034188. You multiply by 100 since you are finding the percent not the decimal and you get about 18.80%
