1. Open the Excel worksheet and select the cell where you want to display the percentage.
2. Type the following formula into the cell:
   
   
   Formula:

   =IF(AND(A1=2500,A1<=4999),[b]1.5%[/b],IF(AND(A1=5000,A1<=9999),[b]1.2%[/b],"")) 

3. In this formula, we are using the IF function to check if the value in cell A1 falls within the range of 2500 to 4999. If it does, the formula returns 1.5%. If not, it checks if the value falls within the range of 5000 to 9999. If it does, the formula returns 1.2%. If the value in cell A1 does not fall within either of these ranges, the formula returns an empty string ("").
4. Press Enter to apply the formula to the cell.
5. The cell should now display the corresponding percentage based on the value in cell A1. In this case, since the value in cell A1 is 4800, the formula returns 1.5%.

That's it! You can now use this formula to determine the percentage for any value that falls within your pre-established set of ranges.