You can build =ISNUMBER() into your formula.
But that would mean having it in there 8 times. It is workable but
=(IF(ISNUMBER(C8),C8,0)*IF(ISNUMBER(C$6),C$6,0)+ ...
quite a long formula.

How about having another row (9) with this
=IF(ISNUMBER(C8),C8,0) etc

Then do your working out against this row instead.
Or you can write out the whole isnumber piece if you can be bothered.

--
Allllen


"Gilles St-Amour" wrote:

Hi

in the following simple formula =(C8*C$6)+(D8*$D$6)+(E8*$E$6)+(F8*$F$6)

sometime the value in the cell c8 or d8 or e8 or f8 is actually a letter(
because of a special requirement), of course I get en error when that happen.
I do not want to remove the cell from the formula everytime because I will
input number sometime in that cell.

I looking to keep the same formulas but with something to disregard the
text value when required or take the number value when there is one in the
cell.

So that way I can copy the formula whitout having the worry about editing
everytime


Thanks in advanced

Gilles