Role of key word sum

Answer 1

Primarily it can be used to total up cells or values. It is best used when you have a large number of cells and/or values to total. If you wanted total all the cells from A5 to A17 your formula, which must be in a cell not included in that range, would be:

=SUM(A5:A17)

You can use it to total numbers in this manner, though it would not be done often:

=SUM(12,45,11,34,19,30)

It would be better to put those values in individual cells and then total them.

To add a mix of cells and values you could have something like:

=SUM(A5:A17,23,19,C20,45,D14:E19)

Although there is no need to do so, it can also be used for other types of calculations that aren't adding values. You can do something like:

=SUM(10-2)

or

=SUM(A5-A11)

However, in those instances it would be better to just do:

=10-2

or

=A5-A11

If you are only adding a small amount of cells, it is quicker to leave out the sum:

=SUM(A1+D23)

It would be better to do:

=A1+D23