2008 Fermat Problem 14

In the diagram, Z lies on XY and the three circles have diameters XZ, ZY and XY. If XZ = 12 and ZY = 8, then the ratio of the area of the shaded region to the area of the unshaded region is

\textbf{(A)}\ 12 : 25\quad \textbf{(B)}\ 12 : 13\quad \textbf{(C)}\ 1 : 1\quad \textbf{(D)}\ 1 : 2\quad \textbf{(E)}\ 2 : 3

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