Here is the set up.

Begin TimeEnd Time Total Time on call
7:00:00 17:15:00 10:15:00
8:00:00 14:00:00 6:00:00
8:30:00 17:00:00 8:30:00
7:15:00 16:20:00 9:05:00
9:55:00 16:30:00 6:35:00
7:00:00 9:00:00 2:00:00
8:15:00 9:35:00 1:20:00
7:00:00 8:15:00 1:15:00
13:00:00 14:30:00 1:30:00
13:30:00 14:50:00 1:20:00
6:30:00 16:00:00 9:30:00
8:15:00 15:50:00 7:35:00
10:00:00 14:30:00 4:30:00
8:00:00 11:00:00 3:00:00
7:00:00 13:00:00 6:00:00
8:00:00 16:00:00 8:00:00
8:00:00 13:00:00 5:00:00
13:00:00 16:00:00 3:00:00
8:00:00 12:00:00 4:00:00
14:00:00 15:00:00 1:00:00
12:30:00 16:45:00 4:15:00

I am trying to sum the total number of hours and minutes in Total time.
Begin and End Time are input as :mm/dd/yyyy hh:mm:ss AM/PM. Total Time is
formatted as hh:mm:ss. Begin Time is subtracted from End Time for Total time
on call.

When I so auto sum for the Total Time at the bottom, I get 7:40:00. I know
there are more hours than 7. what am I doing wrong.