Find the ratio of diameters (or radii, or whatever) of the large spheres to
the largest sphere which fits in the space between four adjecent large
spheres.

A couple of vertices (if not explicitly a dot, then an intersection of two
lines) and a radius are marked on the diagram. Remember this geometry
problem is three-dimensional.

Tim

--
"Librarians are hiding something." - Steven Colbert
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