AMC 8 1993 Problem 21

If the length of a rectangle is increased by $20\%$ and its width is increased by $50\%$, then the area is increased by $\text{(A)}\ 10\% \text{(B)}\ 30\% \text{(C)}\ 70\% \text{(D)}\ 80\% \text{(E)}\ 100\%$