To use the SUM function to calculate the total of a numeric column in a spreadsheet application like Microsoft Excel or Google Sheets, follow these steps:
###### In Microsoft Excel or Google Sheets:

1. **Select the cell where you want the total to appear**: Click on the cell in which you want the result of the SUM function to be displayed.
2. **Enter the SUM formula**: Type the following formula:
=SUM(range)

Replace *range* with the actual range of cells that you want to sum. For example, if you want to sum values in cells A1 to A10, your formula would look like this:
=SUM(A1:A10)

3. **Press Enter**: After typing the formula, press the Enter key. The cell will now display the total of the specified range.
###### Example:

Suppose you have the following numbers in column A:
A1: 10
A2: 20
A3: 30
A4: 40
A5: 50

To calculate the total of these numbers:
1. Click on cell A6 (or any other cell where you want the total).
2. Type the formula: *=SUM(A1:A5)*.
3. Press Enter. The total (150) will be displayed in cell A6.
###### Additional Tips:

- You can also sum non-contiguous ranges by separating them with commas, such as *=SUM(A1:A10, C1:C10)*.
- If you're summing an entire column and want to ignore empty cells, you can simply use *=SUM(A:A)*, which will sum all numbers in column A.
- Using the AutoSum feature (S symbol) in Excel can quickly calculate the total for you. Select the cell below your numeric column and click on the AutoSum button in the toolbar. Excel will automatically suggest the range to sum.
Using the SUM function is a straightforward way to calculate totals in your numeric data!