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by Animats 2335 days ago
Fortunately, the inch is defined as 0.0254 meter exactly. So we have consistency for the really important units.
1 comments

Then which "foot" is exactly 12.000000 inches?
My calculation shows 12 * 0.0254 = 0.30479999999999996 meters. That may be off a little due to IEEE floating-point inaccuracy.
2 * 4 = 8 so the last significant digit should be an ‘8’
Definitely one to cite in the "overreliance on calculators" - the comment you are replying to should have realised that multiplication can't create digits to the right like that!

(Most desktop calculators do it in BCD which would give the correct result, too)

I use Python as my desktop calculator. It has a Decimal module that would have gotten it correct, but that would have been way too much trouble.
Surveyors almost always use tenths (of a survey foot), which is one dead giveaway to which one you're using.
The International one (i.e. Non Survey Foot)

> In 1959, the relationship of the foot to the meter was officially refined as 1 foot = 0.3048 meter exactly.

So 0.0254 * 12.000000 == 0.3048

0.3048 meters / 12 = 0.254