Display time in time format instead of decimal format

Hello all, first timer and as the username may suggest I may not be a regular so hope you don't mind me just popping in now and again.

I am using Excel 2003 and have an import generated from a third party programme which produces time in hh:mm.

A figure of 362hrs 28min (362.28) is shown in Excel as decimal (362.47).

Can Excel do the time in its original format as opposed to decimal?

If it can, has it also the ability to perform non-decimal additions and subtractions?

thanks in advance