You can see the different parts of a nested formula evaluated in the order the formula is calculated. For example, you can see this in the following formula where the function AVERAGE(F2:F5) is shown as its value, 80.
=IF(AVERAGE(F2:F5)>50,SUM(G2:G5),0) as
=IF(80>50,SUM(G2:G5),0)
If the underlined part of the formula is a reference to another formula, click Step In to display the other formula in the Evaluation box. Click Step Out to go back to the previous cell and formula.
To end the evaluation, click Close.
Note The Step In button is not available for a reference the second time the reference appears in the formula, or if the formula refers to a cell in a separate workbook.