When the length of a rectangle is increased by 20% and the width increased by 10%, by what percent is the area increased?
Say L (the length) is 10, and W (the width) is also 10.
The area of this rectangle would be 10 * 10 = 100 square units.
With the newer figures, we get the sides to be L = 12 and W = 11. The area of this is 12 * 11 = 132.
132 is a 32% increase from 100 :D