# Excel Functions

You performed many Excel operations in the examples/exercises discussed above. Excel also has various inbuilt functions to perform different operations. A function can be specified in a cell with an equal sign followed by function name, opening and closing parentheses, and usually some arguments in between, typically a cell range or constant values.

## The function SUM

Numbers were added in the above example using + sign but we can also use the function SUM. This is useful when you have to perform operations on a large number of cells (e.g. add the contents of all the cells from a column or a row). Let’s first see how to perform the same operation as done before, i.e. add the contents of cells D4 and D6:

• Select a cell (say D12);
• Type =SUM( and select the cell D4;
• Place a comma (,) and then select the cell D6. Your worksheet should look like the one shown in Fig. 4. Press Enter to obtain the result. Note that Excel will add a closing parenthesis, if you forget this).

Note that you can simply type =SUM(D4, D6) to obtain the same results. Also note that it is not essential to type SUM in the upper case;

Excel will change the case for you.

Figure 4. Adding numbers using the function SUM.

## Add numbers from multiple cells

The same function SUM can be used to add all the numbers in a column or a row or from multiple cells. Multiple cells can be referred to using the same approach as discussed above but by placing a colon between them instead of a comma. For example, to add all the numbers from cell D3 to D7 type =SUM(D3:D7) in a cell where you want to store the results.

Alternatively, you could also use your mouse to select the cells:

• type = SUM( in a cell where you want to store the results.
• select the first cell you want to refer to (D3) and drag your mouse up to the last cell you want to refer to (D10).
• Place a closing parenthesis at the end and press Enter.

Note that you can use comma as well as a colon to refer to blocks of disjointed cells. For example, you can add cells C2 to C5 and cells D3 to D7 by typing:

= SUM(C2:C5,D3:D7)

## Add numbers in a column

To add all the numbers in a column you can either use the above approach (e.g. by typing =SUM(D2:D7) in the cell where you want to store the results), or alternatively and more conveniently, select a blank cell just below the column of numbers (such as cell D8 to add numbers from column D), click the summation button on the standard Excel toolbar and press Enter.

Note that the procedure to add numbers of a row is same as above except that we select a cell to the right of the row of numbers.