How to Do Addition in Excel

Using the Plus Sign
1. Open the Microsoft Excel 2010 spreadsheet that you want to work with.
2. Click on an empty cell on the spreadsheet, wherever you want the results of your addition to be listed.
3. Type '=' -- the 'equals' symbol -- which indicates the start of a formula, then type in the number or cell reference of the first thing you want to add. If entering a cell reference, place the column letter of the cell in front of the row number, so that the first cell on the spreadsheet is 'A1' and the one under that is 'A2.'
4. Enter a ' ' sign into your formula, then enter the second number or cell reference that you want to add. Continue alternating ' ' signs and numbers or cell references until you have entered all the information you want to add together. Press 'Enter' to complete your formula. The result of the addition appears in the cell.
Using the SUM Function
5. Open the Microsoft Excel 2010 spreadsheet that you want to work with. Click on any empty cell.
6. Type '=' -- the 'equals' symbol -- which signifies that you are starting a formula, then type the word 'sum' and place an open parenthesis at the end of the word. This tells Excel that you will be performing the 'SUM' function on the values in the parentheses.
7. Enter the first number that you want to add, or the first cell reference, followed by a comma, then enter the second value or reference, followed by another comma. Continue alternating values and references with commas until you have entered all the items you want to add together. Enter a close parenthesis and press 'Enter.' The result of your addition appears in the cell.