Was that an Imperial Inch, a US Survey Inch or an International Inch?
"""Dan Paul, writing from the other side of the Pond, objected:
IMHO Screw Metric anything. The original reason for its formal adoption in Europe was to create barriers to trade with the US, just like ISO ratings were. """
NOT TRUE. The big problem of the time is that while everyone used inches and miles, they weren't the same size!!!
To this day there is an Imperial Inch, a US Survey Inch and an International Inch, as well as a Statute Mile and a Nautical Mile. There previously were several other different miles, differing in size by a huge amount. Similar issues exist with ounces and pints.
There never was a Golden Age of Imperial Measurement, where everyone used the same units till the darned Frenchies came along.
OTOH, I don't like that my satnav lets me choose from Miles/Yards, or km/metres. I prefer Miles/Metres when driving... I do people's heights in feet and inches, but weights in kilos... I cook in either imperial or metric...
As long as you remember approximate conversion factors (e.g. 1 mile = 1600 metres, 1/4 mile = 400 meters), it generally doesn't make a lot of difference for most uses. But when it matters, you basically have to use SI units.