The diagonal corner-to-corner distance across a square is measured to be approximately 11 meters. If the sides of the square are exactly 8 meters long, what is the percent error of the measurement? Round to the nearest tenth of a percent.

Sanderson is having trouble with his assignment. his shown work is as follows: − 3 7 7 3 = − 3 7 × 7 3 = − 21 21 = −1 however, his answer does not match the answer that his teacher gives him. complete the description of sanderson's mistake. find the correct answer.