Editing a Formula
When you type a formula into a cell and then hit the enter/return key, the formula will disappear, replaced by a number that's the result of the calculation.
If you need to change the formula, you won’t be able to do so by clicking in the cell, because all you'll see there is a number. If you start typing, it will write over the number.
So how can you edit the formula?
There are two ways:
You can double click on the cell to display the formula in the cell and then edit or retype it there.
Or you can click once on a cell and use the Formula bar above to edit it.
If you click once on a cell that has a formula hidden in it (replaced by a number that's the result of the calculation), the formula you originally typed will appear in the Formula bar above the columns and rows.
For example, click on cell G6, in which in the previous section we typed in the formula =F6-B6. In that cell the number 99 is now displayed.
But look above the columns and rows and you'll see the =F6-B6 formula displayed in the Formula bar.
To edit the formula you can click in the formula bar where the formula for this cell is displayed. Then change the existing formula or type a new one into the Formula bar, press the enter/return key and the new formula will be applied and the numbers will be recalculated in the cell.