<VV> maybe I'm clueless...

[Kinzelman, Andy]

Guys,
Last week I helped a friend pull his drivetrain (broken spider gears).  Just cause I'd never done it - I disassembled the bad diff.  I counted the teeth - 18 pinion & 32 ring.

Can somebody explain the calculations to determine the ratio - I can't get the 3.55 it's supposed to be (I seem to be off by a factor of 2 - why)?
Thanks,
Andy K.
Wisconsin