If you have true Excel time values entered then it's just straight math:

A1 = 0:20 (h:mm format)

=A1*7 (format as h:mm)

A2 = 3:00 (h:mm format)
B2 = 1:10 (h:mm format)

=A2-B2 (format as h:mm)

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Biff
Microsoft Excel MVP


"j lunis" wrote in message
...
How do I perform math calculations on time increments?

For example, 7 * 20 minutes = 2 hours, 20 minutes (2:20),
and 3 hours - 1 hour ten minutes = 1 hour, 50 minutes (1:50).

I know how to format cells to show time but I can't find how to calculate
an answer that shows up as time.