Excel makes calculations based on formulas you enter into cells. When you complete the entry of a formula, Excel displays the results of the formula rather than the formula you entered.
Here are some important things to keep in mind when writing formulas:
If a formula uses cell references to refer to other cells and the contents of one or more of those cells changes, the result of the formula changes, too.
All formulas begin with an equal (=) sign. This is how Excel knows that a cell entry is a formula and not a value.
Formulas are not case ...