# Rollin' Stones Pt. 2

Geometry Level 5

If the radii of the red circle and the blue circle as shown above are 1 and 4 respectively, find the sum of the reciprocals of the radii of the seven green circles.

The answer can be expressed as $$\dfrac{a}{b}$$ where $$a$$ and $$b$$ are coprime positive integers. Find $$a+b$$.

Note: All circles that seem to touch with each other and/or the line are actually tangent with them. For example, the red circle, the blue circle, and the largest green circle are tangent to each other and to the line.

×