Duration info

[A. St. Pierre]

To indicated fractions of a minute on a work page, I use decimals and round up or down to the nearest quarter minute when indicating duration. (e.g. a piece that lasts 5 minutes and 10 seconds I'd mark 5.25) Some administrators leave my indications. Others, objecting to fractions of a minute, either round up or down to the nearest minute, or indicate a range (e.g. 4-5 minutes). What is the correct way to indication durations?

[Notenschreiber]

I don't know if there is a standard format for telling the time, but in any case, giving 5.25 minutes for rounding 5 minutes and 10 seconds to quarter minutes goes against any mathematical sense. This is not how it should be done.