So, let's sum up the counting principle:

If you have a list of events (or choices) that occur
in order (one after another) and there are
 

m

ways to do event 1

n

ways to do event 2
pways to do event 3

then the number of ways they can all be done is

m * n * p

* and you can keep going... as many events as you have!

* The key is that you do event 1, then event 2,
then event
3, and so on.

 

Here's another example:

     You're buying a new car.  You have 3 choices for the model:  The
     Additron, The Subtracto and The Quotient.  You have
5 choices for
     color
: red, blue, black, white and pina colada cream.  You have
2
     choices for transmission:  stick and automatic.  How many choices
     do you have?

3 * 5 * 2 = 30


TRY IT:

You're picking an outfit for school.  In your closet you find 4 pairs of pants, 8 shirts and 6 belts.  Assuming everything matches, how many outfits can you create?