OK, I'm new to this so please check my math

A 1.8" tire, 98 tooth Spurgear
What pinion should I be using.

From what I read on the forum I'm looking for a rollout somewhere near 2.5

(1.8 * 3.14) / (100 / Pinion) = 2.5

I get somwhere around a 44 tooth pinion gear. Does this sound like what most people are using?