Formulas in Excel 2007
 
AutoSum
 
The following illustrates AutoSum:
 
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1.	Go to cell F1.
2.	Type 3. 
3.	Press Enter. Excel moves down one cell.
4.	Type 3.
5.	Press Enter. Excel moves down one cell.
6.	Type 3. 
7.	Press Enter. Excel moves down one cell to cell F4.
8.	Choose the Home tab.
9.	Click the AutoSum button  in the Editing group. 
Excel selects cells F1 through F3 and enters a formula in cell F4.
 
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10. Press Enter. Excel adds cells F1 through F3 and displays the result in cell F4.