Writing a formula to return answers and blank cells.?

If the cell value is less than 10000 then the result is .4 if not .25 but if nothing in cell the result cell needs to be blank. The formula I have so far is =IF(F9<=10000,0.4,0.25)

Unfortunately there’s no way currently for a formula to result in a blank cell. The ideal you can do is an empty string (as above), or you can use NA() instead, which will cause the cell to be ignored in some numerical functions such as charting. (Empty strings, like all text, are treated as zeros.)