=IF(A1="","",B1-A1+(HOUR(NOW())10))

--
HTH

Sandy

Replace@mailinator with @tiscali.co.uk


"julieskennels" wrote in message
...
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