Counting Time

I am trying to sum time. That sounds simple, but excel can't figure out how to do it because all of it's time formatting is based on a 12-hour clock or a 24-hour clock.

Here it goes:

In hours and minutes-

15:25 + 17:57 = 43:02 (43 hours and 02 mins)

If I get past 24:59, It's goes back to 0:00 becaues it thinks it's a new day. No days are involved here. Just adding time like a stop watch. I just want to to continue to count simple hours and mins.

Right now, my cells are formatted in "h:mm@"
" and I have a =sum(number1,number2) as my formula.
If anyone knows how to do this! That would be awsone!

Thankies!