CEMC Pascal, 2007

Geometry Difficulty 2.0 Junior Find the answer Canada

What fraction of the area of rectangle $ABCD$ is the area of the shaded square?

(A) $\frac{1}{15}$ (B) $\frac{1}{8}$ (C) $\frac{1}{10}$ (D) $\frac{1}{4}$ (E) $\frac{1}{12}$

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