Need help on formula calculating start time, end time, start time, end time -
with hours past midnight. What I have so far:

C3 D3 E3 F3 G3
START TIME END TIME START TIME END TIME TOTAL HRS
3:00 PM 8:00 PM 9:00 PM 12:00 AM -16.00 (should be 8
hrs worked)

or

C3 D3 E3 F3 G3
START TIME END TIME START TIME END TIME TOTAL HRS
11:00 PM 7:00 AM -16.00
(should be 8 hrs worked)

G3's formula:
=ROUND(((D3-C3)+(F3-E3))*24.2)

I've attempted to format the work times as [h]:mm but it just converts the
hours to 24 hour time (which isn't used here) - am I doing some incorrect
with that?

Thank you in advance - I've been reading past threads all afternoon but
nothing I've found quite helps yet.

Using Microsoft Excel 2007