How do I total a long list of time calcs?

[Guest]

I am maintaining a time log of time worked using a time-in entry, a time-out
entry and a calculation that subtracts the time-in from the time-out to give
me the hours:minutes worked for each of several officers for each day of the
month. What formula do I use to add the total hours worked for the group at
the end of the month?
Also, I keep a separate duty log of the activities of each officer during
each work day, so there may be as many as 15 or 20 log entries for each
officer for each day of the month. Same question: what formula do I use to
add the total hours:minutes used cumulatively for the whole group for a set
period of time, whether it be for a week, a month, or a quarter?

 

[Guest]

You can sum each day's time as follows with the following assumptions:
Column B = Morning Time In Column D = Afternoon Time In
Column C = Morning Time Out Column E = Afternoon Time Out
In Column F you would have the formula:
=(C2-B2)+(E2-D2). At the bottom of the column you'd SUM the column
Do this for each day of the week with a separate line for each Officer then
summaries the week on a separate sheet with the formula:
=sum(sheet1:sheet7!F2). Do this for each officer.

 

[Guest]

Actually, I can handle the day or week totals, but I have a worksheet that
accumulates every day's entry for an indeterminate period of time. Say, for
example, that there are 1200 rows of entries. Column A=Time In; Column B =
Time Out; Column C = Sum(column B - Column A). I have tried several formats,
which seem to make sense on each line. However, at the bottom of the
worksheet whej I try to get a grand total (=sum(Column C)*24), I get numbers
that make no sense, regardless of what format I try to use. I have entered a
decimal number on the side to test the calculations and have yet to get a sum
of the time calcs that is even close! What am I missing?