2011 AMC 10A Problem 1

A cell phone plan costs \$20 each month, plus 5¢ per text message sent, plus 10¢ for each minute used over 30 hours. In January Michelle sent 100 text messages and talked for 30.5 hours. How much did she have to pay?

\textbf{(A)}\ 24.00 \qquad\textbf{(B)}\ 24.50 \qquad\textbf{(C)}\ 25.50\qquad\textbf{(D)}\ 28.00\qquad\textbf{(E)}\ 30.00$

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