# Changing the data

Before writing your required formula, you need numeric data in different columns or rows of Excels’ sheet. Suppose you want to enter few numbers in a column. Before entry these number you should first confirm the cell reference where you need to enter the data. Let start by entry number in Excels’ cell A1 and A2. For this purpose follow steps given below

1. Click on the cell A1
2. Type 3 from keyboard
3. Press the ENTER or DOWN ARROW key on the keyboard. You will be in Cell A2
4. Now type say 2 from keyboard and press ENTER key

Suppose you want to add these number in Cell C1. You need to write a formula in cell C1. After writing correct formula the content of Cell C1 will immediately changes to addition of two numbers typed in A1 and A2 and used in C1 as formula content.

## Creating Formula in MS-Excel

In Excel, each formula begins with a equal sign (=), see the picture below

Therefore, when creating formulas in Excel, ALWAYS start by typing the equal sign. Equal sign is typed in the Cell where you want the answer to appear. Like image above, follow these steps

1. Click on cell C1 with ARROW keys from keyboard or with mouse pointer.
2. Type the equal sign in cell C1.

After typing the equal sign in step 2, you have two choices for adding cell references to the spreadsheet formula. Note that cell reference is the name of cell you want to use in formula. A1 and A2 are cell references of numbers 3 and 2, respectively.

1. You can type these references in or,
2. You can use an Excel feature called Pointing

Pointing allows you to click with your mouse on the cell contain the data or approaching to a cell reference using keyboard ARROW keys containing your data to add. This will add cell reference to the formula.

After typing an equal sign in cell C3 in step 2:

1. Click on cell A1 with the mouse pointer to enter the cell reference into the formula
2. Type a plus (+) sign. You can also use other operators such as for multiplication use you have to use * symbol, for division / symbol and for subtraction use – etc.
3. Click on cell A2 with the mouse pointer to enter the cell reference into the formula
4. Press the ENTER key on the keyboard

The answer 5 should appear in cell C1.

Note if you have more than one row or column of data then you need to perform calculations on each row or column cell. It is often possible to copy the first formula to other cells. The easiest way to do this is to copy formulas with the file handle.