Standard for rounding measurements

Good Morning,
Does anyone know if there is a standard that discusses rounding of numbers regarding measurements? for example you have a measurement of 12" but want to convert it to mm for labeling purposes.


Thanks in advance,

Ryann

 

Be careful in rounding numbers. Due to rounding, results below can happen:

 

I'm using this freeware for conversion. Unzip it to use it.

 

I have worked with customers who treat significant digits as the only rule (3 place print, 3 place results), customers who specify ANSI E29, and others who look at print +1 (3 place print, 4 place result).

 

LOL...In my experience, each customer has their own "standard".

The only across the board standard I've seen is "only round the final result"...see tony s in post #3 above.

 

...and for playing piano...
(pause, think about it...)...

 

When rounding, one must know to what significant decimal place one is permitted to round off. For example, if we are to round off to one decimal place, the second decimal place (if present) will just be ignored if it is '4' or less. But if the second decimal digit is 5 or more, the first decimal digit will be increased by one before dropping the second decimal place.

In fact this rule applies to any number with any number of decimal places. That is to say that Nth decimal digit should be increased by one if (N+!)th digit is more than 4.