A neophyte's approach to understanding financial problems using calculations that may result in a wide +/- margin of error. Generally Simcoe math is used to broadly prove a point the user is trying to make, allowing a "rough estimate" to masquerade as a definitive answer.
Named after a region in Canada famous for being satisfied with results which may only have a tenuous connection to the truth.
"Guys—I'm just doing a bit of Simcoe math here on the back of this napkin, and it looks like we have just enough cash left for another round of Warthogs!"