The method I found to find the LCM and GCF was the ladder method:
To find the LCM and GCF you can use the same method… You take the two numbers your using, for example, 120 and 200, and you put a multiple of those two numbers outside the lines (10). Below each of the numbers you put the quotient from each, (12) and (20). You then keep repeating this until you are left with two prime numbers at the bottom (3 and 5). To make the next part easier you can create an L on the outside of the ladder. To find the LCM you take all of the numbers at the bottom and the side of the L and multiply them together (10x4x3x5=600). However, to find the GCF you take the numbers from the up & down side of the L and multiply them together (10×4=40). I prefer to use the ladder method to find the GFC and LCM because its very simple and seems less complicated to me. I can understand it better visually than I can with prime factorization.

By: Taylor Richards