How to Enter Sum Formulas into Multiple Cells in Microsoft Excel 2003

1. Select and activate an empty cell. Do this by left-clicking on that cell; you will also need at least two cells that contain data to be summed.
2. Enter the sum formula perquisites into the cell you have selected. Your first part of the formula should read as: =Sum(.
3. Highlight cells you wish to include in the sum formula. These cells will appear in a blue formula box.
4. After highlighting the desired cells to be included in the sum formula, press the enter button to implement this new formula.