I want to copy a date field "10/18/2005 8:05" into another column and change
it to a number (minutes) so 8:05 (8 hours & 05 minutes) reads as 485 minutes
- and I would take the 485 and divide it by another value to yield gallons
per minute.

The date field is downloaded from another source so I cannot change it's
format direcetly. How do I change it after I copy it into a number format?