They're almost always rounded, not much of a point in having a 43.434098 mm measurement when it can simply be 43.5mm. Unless of course you're measuring something that requires precision such as slotting fret slots, that's a whole different story!
Use this site for converting, or google.
http://www.initium.demon.co.uk/converts/metimp.htm
Hehehe, 43.434098 would round to 43.4, not 43.5.
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