Meeting Duration between two columns to a seperate worksheet

[rolandeckstein]

if i wanted to add an abs value formula into that, where would i put it. As of right now im using the same formula for meeting duration, subtracting one column from the other. and its not pickin up a select few pairs that come up negative, for example, 1:00 pm to 11:15 AM, when subtracted

= F10-D10
="11:15 AM" - 1:00 PM

it comes to -0.07292

therefore i need to add an absolute value into this formula:

=SUM(IF(July!F4:F1000003*July!D4:D1000003,(July!F4:F1000003-July!D4:D1000003<=0.5)+0))

if i wanted to add an abs value formula into that, where would i put it and is that what would do the trick to find out the correct meeting duration.

 

[p45cal]

It's probably because the times are reversed; a meeting from 1pm to 11:15am is an all nighter. There should be no problem at all subtracting times which don't cross midnight.
However, if the entries are reversed a simple =ABS(F10-D10) should do it. but I wouldn't do it, I'd want to be alerted that times were swapped.