How can I show time spent?

[L]

In an Excel worksheet, I have 2 columns, 'start' and 'end' time; in the 3rd
column, I need to show time spent on a task. I'm sure this can be done, just
not sure how...any suggestions would be appreciated, thanks.

L

[Dav]

Just subtract the start time from the finish time
eg if start in a3 and finish in b3

b3-a3 then copy down to the other cells

format the cells as custom and type the following [hh]:mm

regards

Dav