Urgently need help modifying this formula:

=IF(F13="NO",((D13+E13)-(B13+C13))*24,0)



Is it possible to have Excel subtract 1.5 hours from the start time and add .5 hours to the end time? A pilot duties on at 0800 for instance, and off at 1600. His per diem starts at 0630 and ends at 1630, so he works 8 hours but gets paid a per diem of 10 hours for meals. That example is straight forward but I am trying to avoid math errors when he duties on at 0817 for instance, and has to calculate 1 hour and thirty minutes prior to that time to enter it manually in his per diem claim spreadsheet. Is there a way to modify the formula to do that? I would like to be able to enter 0800 and have 0630 populate that field or have the calculation of total hours total to 10 instead of 8. Your assistance is appreciated.

Attached Images

Sample.jpg (16.5 KB, 15 views)