2007 AMC 12A Problem 1

One ticket to a show costs \$20 at full price. Susan buys 4 tickets using a coupon that gives her a 25\% discount. Pam buys 5 tickets using a coupon that gives her a 30\% discount. How many more dollars does Pam pay than Susan?

\textbf{(A)} \ 2 \qquad \textbf{(B)} \ 5 \qquad \textbf{(C)} \ 10 \qquad \textbf{(D)} \ 15 \qquad \textbf{(E)} \ 20

Full credit goes to MAA for authoring these problems. These problems were taken on the AOPS website.