Trent told his friends it would take him 90 minutes to mow the lawn. It only took him 75 minutes. What is his percent error?

1 Answer
Nov 3, 2017

His percent error is #16.bar6%#

Explanation:

Trent estimated his time to be #90m#

Actual time was #75m#

Error was #90m-75m=15m#

Fractional error was then #(15cancelm)/(90cancelm)#

So #%# error is #cancel15/(cancel(90)6)xx100=100/6%=16.bar6%#