p 29, Q16
A number of interlocking rings each 1 cm
thick are hanging from a peg. The top ring
has an outside diameter of 20 cm. The
outside diameter of each of the outer rings
is 1 cm less than that of the ring above it.
The bottom ring has an outside diameter
of 3 cm. What is the distance from the
top of the top ring to the bottom of the
bottom ring?