Conditional Formatting Formula

[heinojt]

Please help, I need to write a formula for the following: if cell A2 is between 0-10% then A3 must =5% of A1, but if A2 is between 11- 20%, then A3 must = 7% of A1

 

[Peter_SSs]

Welcome to the MrExcel board!

Your actual question does not seem to have anything to do with "Conditional Formatting Formula". Did you just mean "Conditional Formula"?

You didn't say what to do if A2 is greater than 20% or whether that is possible with your data.
Assuming A2 cannot be bigger than 20% then try

=A1*IF(A2<=10%,5%,7%)

If A2 can be bigger than 20% then perhaps something like this?
..or explain what should happen for >20%

=IF(A2<=10%,A1*5%,IF(A2<=20%,A1*7%,"A2 is bigger than 20%"))