Excel offers a slew of basic formulas you can use to make compiling data easier. These formulas can be easily accessed in the “Formulas” tab and are a simple way to do everything from adding totals to formatting dates. If you are new to Excel and just learning, or need a refresher on what to do, here are some common formulas you can use to create effective spreadsheets.
An Example: Adding Numbers In Different Cells
To add two cells together so the answer appears in a third cell:
 Type an equal sign in the third cell (let’s call this cell C1).
 Click on the first cell (let’s say A1) with the mouse pointer.
 Type the plus sign (+) in the third cell.
 Click on the second cell (let’s call this B1) with the mouse pointer.
 Press the ENTER key on the keyboard.
 The sum should be present in C1.
 Even though you see the answer in C1, if you click on that cell you will see our formula in the formula bar above the work area.
You can also do this manually. Either way, the formula should look like this =(A1+B1)
You can do this for any number of cells. If you are working with more than two cells in a column or row, you can accomplish the same task by typing in a formula using a colon. That formula looks like this =SUM(A1:A9) or =SUM(A1:D1)
There are several other formulas that operate the same way, and you can create them by substituting the following characters for the addition (+) sign.

Subtraction Negation 
3–1 –1 

Multiplication  3*3 

Division  3/3 

Percent  20% 

Exponentiation)  3^2 
These are the most basic variants on common excel formulas. As time goes on and you become more familiar with Excel, you will be able to manipulate data in several different and exciting ways. Once you become accustomed to working with formulas, you’ll find out how much easier they make your work!