2013 Pascal Problem 6

Erin walks \frac{3}{5} of the way home in 30 minutes. If she continues to walk at the same rate, how many minutes will it take her to walk the rest of the way home?

\textbf{(A)}\ 24\quad \textbf{(B)}\ 20\quad \textbf{(C)}\ 6\quad \textbf{(D)}\ 18\quad \textbf{(E)}\ 12

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Full credit to this problem is given to the CEMC, you may view all Pascal contests here.