OpenOffice Calc, the spreadsheet program offered free of charge by openoffice.org, allows you to perform calculations on data entered into the spreadsheet.

You can use OpenOffice Calc formulas for basic number crunching, such as addition or subtraction, as well as more complex calculations such as payroll deductions or averaging a student's test results.

In addition, if you change the data Calc will automatically recalculate the answer without you having to re-enter the formula.

The following step by step example covers how to create and use a basic formula in OpenOffice Calc.

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Entering the Data

The following example creates a basic formula. The steps used to create this formula are the same ones to follow when writing more complex formulas. The formula will add the numbers 3 + 2. The final formula will look like this:

= C1 + C2

**Note**: For help with this tutorial refer to the image above.

- Type a
**3**in cell C1 and press the**ENTER**key on the keyboard. - Type a
**2**in cell C2 and press the**ENTER**key on the keyboard.

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Enter an Equal Sign

When creating formulas in Open Office Calc, you **always **start by typing the equal sign. You type it in the cell where you want the answer to appear.

**Note**: For help with this example refer to the image above.

- Click on
**cell C3**(outlined in black in the image) with your mouse pointer. - Type the
**equal sign**(=) in cell C3.

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Add Cell References

Following the equal sign, we add in the cell references of the cells containing our data.

By using the cell references of our data in the formula, the formula will automatically update the answer if the data in cells C1 and C2 changes.

The best way of adding cell references is by using the mouse to **point and click** on the correct cell. This method allows you to click with your mouse on the cell containing your data to add its cell reference to the formula.

After the equal sign added in step 2:

- Click on
**cell C1**with the mouse pointer. - Type a
**plus**(**+**) sign. - Click on
**cell C2**with the mouse pointer. - Press the
**ENTER**key on the keyboard. - The answer 5 should appear in cell C3.
- Click on
**cell C3**. The formula is shown in the**input line**above the worksheet.

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Mathematical Operators in OpenOffice Calc Formulas

Creating formulas in OpenOffice Calc is not difficult. Just combine the cell references of your data with the correct mathematical operator.

The mathematical operators used in Calc formulas are similar to the ones used in math class.

- Subtraction - minus sign (
-)- Addition - plus sign (
+)- Division - forward slash (
/)- Multiplication - asterisk (
*)- Exponentiation - caret (
^)

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OpenOffice Calc Order of Operations

If more than one operator is used in a formula, there is a specific order that Calc will follow to perform these mathematical operations. This order of operations can be changed by adding brackets to the equation. An easy way to remember the order of operations is to use the acronym:

BEDMAS

**The Order of Operations is:**

**B**rackets**E**xponents**D**ivision**M**ultiplication**A**ddition**S**ubtraction

**How the Order of Operations Works**

Any operation(s) contained in brackets will be carried out first followed by any exponents.

After that, Calc considers division or multiplication operations to be of equal importance, and carries out these operations in the order they occur left to right in the equation.

The same goes for the next two operations — addition and subtraction. They are considered equal in the order of operations. Whichever one appears first in an equation, either addition or subtraction, is the operation carried out first.