One of the guest rooms in my house has two walls that are 15'6" by 8 ft, and two that are 12'3" by 8 ft. When buying paint for the walls, I estimated the wall area to be about 450 sq. ft. Find my percent error.

Question

I got 1.41% but i have a question on tue next one.
Use the actual error in the estimate to find the dollar value of wasted carpet.

Answer 1

actual area ... 2 [(15.5 * 8) + (12.25 * 8)] = 444

% err ... [(450 - 444) / 444] * 100% ≈ 1.35%