The estimated range highlights. Edit the range by left-clicking and dragging the cursor over all values in the row to sum, if desired. The selected rows are highlighted.

SUM is the spreadsheet equivalent of an open invite: it welcomes everything into the total, whether it belongs there or not.

How to Do the Sum of an Indefinite Series in Excel. The Microsoft Excel program includes a variety of mathematical formulas that you can apply to any cell in a spreadsheet.