Time Difference Calculation and Sum Problem

[Dudley Wright]

I have a spreadsheet wherein we log the Start Time of an event, and
the End Time of the same event. I currently have 539 rows, starting
in row 2 of data formatted as hh:mm. What is needed is to calculate
the elapsed time, which I can do, and to calculate the total elapsed
time for all 539 rows, which eludes me. Perhaps the method for
calculate elapsed time for individual rows might need to be changed,
or formats are incorrect to accomplish this, but I just can make no
sense of the sum of all the elapsed times.

A small sample of data would be:

Start End
14:35 16:22
07:35 11:45
22:50 03:18

This data set continues to row 540, with field headers in row 1.

Can anyone give me some guidance .

Thanks in advance,
Dudley

 

[Frank Kabel]

Hi
format the target cell with the custom format:
[hh]:mm
to prevent a rollover after every 24 hours