How to Use Auto-Sum in Spreadsheets

Step 1: Open the file, click 'Edit', convert it to 'Edit Mode'. Like the fillowing:

Setp 2: Click the button ‘Tools’.

Step 3: In "Tools", there is an ’AutoSum’ option below ‘Data’ Tab.

Step 4: Click ’AutoSum’ to find the option 'Sum'.

Step 5: Set the range of cell where ought to be sumed. You can drag the cells or input the cell range.

Step 6: At last, click enter to confirm.