Adding a formula into a number format cell

I'm looking for a way to create a custom number format that will allow me to select a group of cells and change it to what i want.


Example: I have a cell that has the [h]:mm format to represent a duration of time worked. I currently am changing them to the general format the having to go to another cell and multiply that cell time 24 (=L5*24) to get the time duration I want.


Is there a way I can make a custom format that will shortcut all this into one or two actions?

in your cell =SUM(C2:N2)*IF($A$1=24,24,1)
and CF General if =$A$1=24