Three concentric circles are shown. The two largest circles have radii of and If the area of the ring between the two largest circles equals the area of the smallest circle, determine the radius of the smallest circle.
+605 \(13^2\pi-12^2\pi=169\pi-144\pi=25\pi\rightarrow |\sqrt{\frac{25\pi}{\pi}}|=\boxed{5}\)
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