j,

=IF(CheckOut-INT(CheckOut)=0.417361111110949,INT(CheckOut-CheckIn)+1,INT(CheckOut-CheckIn))

I named the in and out cells. Change the CheckIn and CheckOut to reflect
your cells.
7/14/05 5:30:00 PM 7/14/05 5:30:00 PM
7/17/05 10:01:00 AM 7/17/05 10:00:00 AM
3 Days 2 Days

This formula gives your customer's a one minute grace period, in other words
at 10:01 AM, it adds another day to the bill. I'm not sure how close you want
to cut it. Microsofts date is in the form of a serial number. The integer
portion is the month, day and year, while the decimal portion is the time.
You can change the decimal value in the formula to suit your own "grace
period"

Roy

"julieskennels" wrote:

I want to perform the following calculation.
a & b are dates; c is number of days to be charged for
Check out is 10 am
if a is blank ; cis blank
If current time is after 10am result is b-a+1
if current time is before 10am result is b-a
Having trouble with the time part - sure it is something simple