Two concentric circles are drawn, as shown in the diagram. Concentric circles share the same point as their centre. The radius of the smaller circle is a third of the radius of the larger circle. The top half of the larger circle which is outside the smaller circle, is shaded in grey. The ratio of the grey shaded area to the area of the smaller circle in its simplest form is . What are the values of and ?
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Junior Mathematical Olympiad 2017 (2017)
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