This is not a problem in math so much as in process engineering. ONE standard of communication for allparticipants in a given dialogue usually works better than having to introdice a real-time analyze-and-translate-if-necessary loop. Why not have a standard report in SECONDS ONLY and require the timer to write it down before h/she reports it, so there is no fuzziness about the step from the stopwatch to the reported number?

A