When using formulas in Excel you can add, subtract, multiply, and divide. Use simple Excel formulas to also make cell references in Excel.
A simple formula in Excel contains one mathematical operation only: one number plus a second number equals a third number. Writing a simple formula is no more difficult than that: 1+1. The only difference in Excel is that all formulas must begin with the equals sign (=). It is not enough to type 1+1 in Excel because what will appear in the cell is "1+1." You must begin the equation with an equals sign, or =1+1. This holds true for any formula—simple or complicated—that adds, subtracts, multiplies, or divides.
Let's add two numbers to create a third: 128+345=473. In Excel, this would be expressed by the formula =128+345, as shown below.
Excel will not always tell you if your formula contains an error, so it's up to you to check all of your formulas. To learn how to do this, you can read the Double-Check Your Formulas lesson from our Excel Formulas tutorial.