factors and gcf

Factors and GCF (greatest common factor)!!!!!!!!
The first thing you should know before doing factors and GCF'S is what a factor is. In a nutshell, the definition of a factor is a number you multiply by another number to get your product.
Now you can start to learn how to do factors. Say the two numbers you have are 4 and 20. All you need to do is make a list of all the numbers you can multiply to get to the number you want and then find the the largest number they both have.
EX. 4 = 1,4,2,2
20= 1,20,2,10,4,5
So greatest common factor of 4 and 20 is 4. Sometimes you can just find the factors for the smaller number and see if any of those numbers can go into your larger number.
If you are sitting at your computer reading this thinking when am I going to use this, heres a thought. When you have a large fraction, you can find the GCF to simplify your fraction. To find out more about this awesome topic, you should go to one of my favorite sights!!!!! http://www.purplemath.com/modules/factnumb.htm