Question

How do you find the gcf

Answer 1

Divide the number by prime numbers that go into all 3 or 2 numbers. Then you multiply the numbers you used to divide by are multiplied together. Ex: 2I_18_30_24_
                                                                                                       3I__9__15__12__

                                                                                                 2x3=6

6 is your Greatest Common Factor  

Answer 2

1).  List all the factors of the first number.

2).  List all the factors of the second number.

3).  Make a "short list", of the factors that are on both lists.
     These are the 'common' factors.

4).  Find the biggest number on the short list.
     That's the 'greatest common factor' of the original two numbers.