Re: [math-fun] approximating pi by 1

James Propp <jamespropp@gmail.com> wrote:

(Of course when we're doing dimensional analysis we ignore dimensionless factors like pi, but that's not what I mean; I'm talking about replacing pi by 1 in calculations where getting an answer that's off by just one order of magnitude is good enough.)

Not Feynman, Fermi. See https://what-if.xkcd.com/84/