Adding military time from multiple cells
 

I am working on a spreadsheet to track total times that our local fire station is out on a call. I have to multiply the number of responders to the time to get an overall manhour time for the run. Once it goes over 24 hours it gives me a number other than what it should be. I then have to add all the times up for each run and I get the same problem after 24 hours. An example would be "T5" has the number of responders that needs to be multiplied into "V47" which is the run time. I have 5 responders with a run time of 5 hrs and 50 min. and it gives me a answer of 5 hrs and 10 min. Not sure what to do, please help.