Hi Everyone...
I work for a finance company who offers vehicle financing. We are trying
to track how long our approval/turn down process takes from the time that we
get the application until we've made our decision. There are a few things
that I need to accomplish, and any help would be GREATLY appreciated!

1) I currently have 4 columns set up. Column A= application date. Column B=
application time. These represent the date and time that we receive the
application. Then I have Column C= decision date and Column D=decision time.
These obviously represent the date and time that the application is either
approved or turned down. There are times when we receive an application on
(example of) Monday at 8:00 pm but don't make a decision until (example of)
Tuesday at 3:00 pm. I need a formula that will show how long in hours it
took for us to make a decision, but need to be able to account for the fact
that not all applications are received and decided on in the same day. So,
the above referenced application would need to show that it took 19 hours to
make a decision, then I would have another column set up to subtract the 12
hours that we were closed to keep the data accurate.

2) If I decide to merge the date and the time into one cell, which I'm
familiar with, would the formula be the same?

3) If there is a better way to do this, I'm open to suggestions!

THANKS IN ADVANCE FOR ANY AND ALL HELP!