Factors and GCF

First you need to know what factors and the GCF are. Factors are numbers that divide into a lager number evenly and the GCF (greatest common factor) is the biggetst number that fits into all the numbers you are working with evenly when you divide them. For example if you had numbers like 2, 10, and 18 you could say that 10 is the GCF, but 10 doesn't fit into 18 evenly. One way to do this is to list all the factors of the biggest number which now is 18. You would have 1, 2, 3, 6, 18 as your list. Now you see which number fits into all the numbers evenly. So the answer is 2.