We may do this by either typing or by using the mouse to drag over the range. In the Function Wizard (Step 1) dialog box under Function category select Statistical and under Function Name select AVERAGE as in Figure below.
The function wizard will take you through setting up the fields in the function step by step. Select Cell D2 and open the Function Wizard either by opening the Insert menu and clicking 'Function' or by clicking on the function icon to the left of the address bar. Write some numbers in cells A1 through A3. Let us assume that we want to take the average of the values in cells A1:A3 and write the result in cell D2. The Average function will calculate the average of all the numbers you list in the parenthesis. In the following example, the 'Average' Function has been used as an example. Use the mouse to click on each Function category and explore the Functions. To use the Function Wizard you can either choose Function from the Insert menu or you can click on the Function Wizard button 'fx' located on the Standard toolbar.
The function wizard opens all of the functions in Excel, through sub-menus and categories.
