Making formulae function throughout worksheet

[Guest]

I am currently working on setting up a call cost register for my workplace.

Currently, the first cell in columns D, E and I have a formula in them used
to calculate total time of the call, the number of 6 minute units the call
used and the total cost of the call.

However, is the register is expected to be an ongoing thing, I need those 3
formulae to function in ever cell of their respective columns.

Is there any way that this is possible, and if so, could someone please
explain how to set it up.

 

[Guest]

I am currently working on setting up a call cost register for my workplace.
Currently, the first cell in columns D, E and I have a formula in them used
to calculate total time of the call, the number of 6 minute units the call
used and the total cost of the call.
However, is the register is expected to be an ongoing thing, I need those 3
formulae to function in ever cell of their respective columns.
Is there any way that this is possible, and if so, could someone please
explain how to set it up.

Assuming you have this formula in F1: =D1*E1

Then just use something like this instead in F1:
=IF(OR(D1="",E1=""),"",D1*E1)

Fill F1 down to say, F100,
to cater for the max expected extent in cols D and E

Col F will display "nothing", i.e. ""
until data* is input in both cols D and E
*or the formulas in cols D and E evaluate to other than ""


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