As a graduate of the Georgetown School of Foreign Service, I feel it's my duty to point out that the major difference between the core requirements of the SFS and the College of Arts & Sciences is that you have no math or science core requirement in the SFS. I think you end up having econ take the place of math & science in the SFS's core requirements, but the basic econ courses (micro, macro, int'l trade, int'l finance) do not require anything more than knowledge of algebra.

So yes, it is quite possible to get a political science degree and not know a single thing about math or science beyond your high school education.