In cel C, try this one:
=IF(B1/A1=12,B1,(12-A1))


"Salesmaster" schreef in bericht
...
hello all,

I need to answer a question in a particular cell.If value in cell A is <
12% of Cell B how much more is needed to be in cell A to be = or 12 % of
cell b but if cell A is = to or then 12% cell b leave answer blank.

I thank anyone thank can help me in advance since thi is day one excel for
me