2007 Pascal Problem 14

At Webster High School, the ratio of males to females writing the Pascal Contest is 3 : 7. If there are 21 males writing the Contest, what is the *total* number of students writing?

\textbf{(A)}\ 30\quad \textbf{(B)}\ 25\quad \textbf{(C)}\ 49\quad \textbf{(D)}\ 70\quad \textbf{(E)}\ 79

If there are no answer choices shown, enter a numerical answer.

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