alt Hacker NewsCan you give an example? I can't imagine calculating conversions between inches and feet to be easier than using millimeters/centimeters/meters. Or using mostly millimeters in construction in Europe. You have one unit to deal with that generally tends to be integer value. No need to fractions.
You don't convert. Airplanes are designed in mm and you never need meters. Houses are in inches - we say 92 5/8. Or sometimes 2 feet 3 inches. Our measurement tools have both marks so we can do it without coversion.