|What you're technically looking for is a "Nested IF Function;" basically it is where you insert a function as an argument for another function.... |
What I've done here is "nested" a second IF function in the "IF FALSE" argument. So, walking though the function it will read as: IF B61 is great than or equal to 30, if this is true it will return the value of 600, if this condition is false, it will preform the next IF function, asking if the value is greater than or equal to 25... and so on.
A couple of concerns: Are you planning on making more "Bonus Brackets" for any persons under 20 sales (ex:11) or any persons over 30sales?? Also, are you planning on entering this function into one cell and then simply copying it over or down to other adjacent cells? if so, it may be best to use a different type of Cell Referencing for B61... If you'd like, you can PM. It would be very helpful if I could see an example of the spreadsheet.
Hope this helps!! Best of luck!