Step 1 - Preparing to enter an
equation - You are ready to build your own function (an
equation). There is a single keystroke that informs Excel of your
intention. Press the equal key (=). If you can write the equation,
Excel can perform the calculation. This module will deal with four
simple functions; add, subtract, multiply and divide.
Step 2 - Writing an addition equation -
If you were to state the process for adding the numbers in
column B it would be "six plus three." The equation could be
written exactly like that
(=6+3)
and Excel would display the expected answer, 9. However that
equation would be useless if the numbers in either B2 or B3 were
changed. When writing your own equation, use cell
addresses.
=B2+B3

When writing the equation, clicking in cell B2
displays B2 in the equation. If you have written the equation
correctly you may accept it by pressing the Enter/Return key or by
clicking on the green check mark. If you change your mind, click
on the red X to cancel the operation.
Step 3. Writing other simple functions -
Symbols for the four basic mathematical functions are:
- addition +
- subtraction -
- multiplication *
- division /
Step 4. Task - Prepare a worksheet with
the data displayed under Step 1. Enter the proper equation under
each set of two numbers. Do not look at step 5.
No! Don't look yet! :-)
Step 5. Compare - Compare your results
to those shown below:
This was not a math quiz, it was an equation
writing quiz. If something was unclear ask someone near you, ask
your teacher, then ask
me.
Step 6. Combining functions - If you can
write the equation, Excel can perform the math. To illustrate this
we will write an equation which will add several numbers, divide
to get an average, and then take a percentage of that number to
provide a weighted component of an equation used to average
grades.
Scenario: Bill took three tests scoring 88, 76,
and 58. The average of his tests counts as half of Bill's grade.
What number value has Bill achieved toward his term
grade?
Next Module: Worksheet Basics - Percentage and
Absolute Cell Reference