The width, length, and height of a rectangular prism are each increased by 10%. What is the percent increase in the surface area of the prism? Express your answer to the nearest whole number.
(1.13-1) x 100%=33 %
The scale factor = (1.1)
If we let the original surface area = A
Then the new surface area = A (scale factor)^2 = A ( 1.1)^2 = 1.21A
So
The % increase in the surface area =
(1.21 A - A) A ( 1.21 - 1)
__________ = ___________ = .21 = 21%
A A
