2015 Fermat Problem 14

In the diagram, PQRS is a square and M is the midpoint of PS. The ratio of the area of \triangle QMS to the area of square PQRS is

\textbf{(A)}\ 1:6\quad \textbf{(B)}\ 1:4\quad \textbf{(C)}\ 1:3\quad \textbf{(D)}\ 1:8\quad \textbf{(E)}\ 1:2

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

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