First let's find the GCF of 27, 36, and 72: -->Find the factors of each number: 27: 1, 3, 9, 27 36: 1, 2, 3, 4, 9, 12, 18, 36 72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72 -->Now look for the factors they have in common. 1, 3, and 9 -->Now see which one is the biggest number in value 9 --> So therefore, 9 is the GCF
Now let's find the LCM of 7, 4, 10, and 12 -->Start listing all the multiples of of each number 4: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40... 420 7: 7, 14, 21, 28, 35, 42, 49, 56, 64, 70... 420 10: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 120... 420 12: 12, 24, 36, 48, 60, 72, 84, 96, 108, 120... 420 (sorry got bored of typing so I fast forwarded at the '...'s) --> The least number in value that they have in common is the LCM of those numbers The LCM is 420
*Just saying that took forever to do that LCM part but not way too long thank goodness :p
LCM= 420 When you list the numbers and their multiples, you keep on listing it until you get a same #. GCF= 9 The GCF is 9. Try the birthday cake method- :0
First, put all the #s together and organized on a rectangular box.
Then, see what goes into all of the #s. Write that # down on the left side of the "cake" (the box). Keep on doing it until their is no common # that goes into them both.
You then add all of the #s that are on the side of the birthday cake.
*If that is the only # that goes into the #s, it is just that #.
