Time assistance needed surrounded by Excel.? I'm not even sure how to explain this. I'm creating a timesheet.

I'm not even sure how to explain this. I'm creating a timesheet. The staff can work over a 24 hour period. Officially on the rota, staff sign past its sell-by date at midnight and on the rota it is recorded as 12:00 AM. Starting at 1:30 PM the previous afternoon. I own one column split in to two. For example, Monday the 1st split into two, the first reading 1:30 PM, the second 12:00 AM. I subsequent have a unnoticed column that adds the hours worked. When I input 12:00 AM, it minuses the total to some extent than adds it.
I am currently using a formula along the lines of:

=(B3-C3)*24 and own to reverse this in charge to read positve or minus.

If in the first column the member of staff starts at 9am and finishes at 5am, it calculates it fine, no problem, it's simply when it starts in the afternoon till midnight.
I kinda involve to know how to make IT know when to reverse it and not - ideally lacking using dates!

Please back :)

Thanks

Answers: Here's an example:

Our "time" cells are of the Excel type "1:30 PM." So:
cell B3 is the start time
cell C3 is the finish time
the equation, surrounded by cell D3 is =MOD(C3-B3,1)*24

Cell D3 is just a number type near 2 decimal places.

The function will handle afternoon to evening (or vice-versa) so there's no have need of to "reverse" anything.

See if that works for you.

I've just tested it on these hypothetical times and it works OK.

1:30 PM 12:00 AM = 10.50 hours
9:00 AM 5:00 AM = 20.00 hours
5:00 AM 9:00 AM = 4.00 hours
3:30 PM 12:00 AM = 8.50 hours
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