Yeah, that's basically how I remember it, though it's not always stats--the terms are used in other fields of math as well. A first calculus class typically includes a proof that the limit of the sum of an infinite geometric series (a + ar + ar^2 + ar^3 + ...) tends towards a/(1-r) where a is the first term and r is the ratio of successive terms, provided that -1 < r < 1. (Otherwise the series diverges and the limit isn't defined.)