~ is epsilon? I'm not up on notation like that, I was assuming it was being used as shorthand for approximate, which is the equal sign made of tildes when using a keyboard that can generate it (mine can't and neither can most on screen keyboards, though I copied one from a search, just don't know if it'll show right) like so ≈

I do agree, btw, that in any situation where you'd be using fractions for sizable things that a third being .33 of whatever is "close enough", if you have actual units involved.

I would still point out that when units aren't in play, fractions tend to work better since it's way harder to fold strings into tenths. Not impossible! Just harder than halves or thirds (which can then be redone got quarters, sixths, etc if needed). That's mostly for day to day lengths, since weights aren't going to be usefully divided by fractions or decimals, and liquid measure is way harder to be accurate with unless you have a very even container