Math
posted by Angie .
This rectangle represents a tabletop. Its measured length is 48.5 ft, and its measured width is 36.5 ft.The relative error of these measured dimensions is 0.04. What is the relative error when computing the area of the tabletop?
a. 0.0082
b. 0.082
c. 0.82
d. 8.2
I think the answer's supposed to be b., but how do you get it?

(1.04)^2 1 = 1.082 1 = 0.082