If the time column is in "true" XL recognizable time format as you stated
(hh:mm:ss), then all you have to do is format your total cell, or even each
individual cell (if you choose) to the custom format:
[ss]
The square brackets prevent the seconds from rolling over into minutes, and
then over into hours.

You could also link your individual time cells to a separate column, and
format that column to [ss], so that you might have a displayed comparison.
--
HTH,

RD

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"Ianukotnorth" <Ianukotnorth@discussions.microsoft.com> wrote in message
news:1B66EA6B-D025-4BC0-9260-DD4BE56CFD80@microsoft.com...
> I wish to compare the cost of telephone calls between various telephone
> service providers available to me.
> I have downloaded a list of itemised call made by me from my present
> provider and I wish to compare the cost of each call if I had used
> alternative providers.
>
> I'm OK with the basic mathematical formulae - but I need to convert a
"Call
> Duration" in "hh:mm:ss" format to seconds.
>
> (I could use the "Text to columns" facility and then multiply the "
Minutes
> Column by 60 and the hours column by 360 - and add the three columns
together
> but feel this is clumsy when there must be a "nicer - easier way)
>
> Thanks for your help.
>
> Ian M