With the start time in A1 and the end time in B1:

=(B1-A1)*24

Format as Number. It will probably be formatted as time automatically;
ignore that and format as number.

--
Kind regards,

Niek Otten

"GregJ" wrote in message
...
Thanks Niek'
Exactly which formula should I write? Let's say I start the contact at
10:43
and finish it at 11:01 and I need the calculation in tenths of an hour.
Please advise which formula I should use and the exact context of this
formula and which one to use.
Thanks again

"Niek Otten" wrote:

Reverse the calculation: End time minus start time.
=(a1-A2)*24
Format as general or number, not time

--
Kind regards,

Niek Otten

"GregJ" wrote in message
...
I would like to write a formula where I would input the starting time of
a
project or customer call minus the finishing time and then convert that
amount of minutes to tenths of an hour.
Any ideas how?
Thanks
Greg Johnson