The easiest way to learn about arrays is to look at a few examples. For instance, you can calculate the averages by entering a single array formula. We entered a single array formula in the selected range F4:F8. This particular example might be used to help protect the formulas from tampering because modifying individual formulas in cells that are part of an array is impossible. To enter this formula, do the following:

1 Select the range F4:F8.
2 Type the formula into the formula bar.
3 Press Ctrl+Shift+Enter.

The resulting single array formula exists in five cells at once. Although the array formula seems to be five separate formulas, you cannot make changes to any one formula without selecting the entire formula; that is, the entire range F4:F8.