put product in A1
put percentage in B1
put =A1/B1-A1 anywhere.


Does not matter if you use units of volume or weight.
--
Gary's Student


"BRUCE" wrote:

> I AM TRYING TO CREATE A FORMULA FOR CHEMICAL DILUTIONS. THE FORMULA NEEDS TO
> BE ABLE CREATE A PROPER MIXTURE OF PRODUCT AND WATER EVEN THOUGH THE AMOUNT
> OF PRODUCT MAY VARY, THUS CHANGING THE AMOUNT OF WATER NEEDED