On Tue, 21 Jul 2015 11:14:22 +0100, Roderick Stewart
I remember a magazine (Studio Sound I think) that had to make
frequent reference to quarter inch tape, but insisted on calling it
6.25mm tape. I don't know it they were not very good at calculations,
or if they thought for some reason that 6.25 looked nicer than 6.35.
Approximation by truncating unnecessary digits is perfectly
reasonable, but including digits with wrong values is something else.
It's blindingly obvious that they thought 1 inch = 25mm when it obviously
doesn't. Hence 1/4 inch = 6.25mm.