Percents

1.

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?

22%

81.20%

23.16%

18.80%

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%