# Rotating a Smaller Circle outside a Larger one!

Geometry Level 5

Two circular discs have radii 8 and 28. The larger disc is fixed, while the smaller disc rolls around the outside of the larger disc. In their original positions, point $$A$$ on the smaller disc co-incides with the point $$B$$ on the larger disc. The least number of rotations that the small disc makes about its centre before $$A$$ and $$B$$ again co-incide is:

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