Sixth graders always confuse GCF and LCM. We were brainstorming one afternoon and came up with an idea to help the kids remember GCF and LCM. This is really helpful when a testing question asks for the LCM of 15 and 21, and most the kids see these numbers and want to answer, "It's three!"
Well, it's not. That's the GCF.
So, we use a graphic that looks like the one to the right (hope you can see them). The F is morphed into a division sign, and the M is morphed into a multiplication sign. The division sign is a reminder that common factors are numbers that DIVIDE into 15 and 21. The multiplication sign is a reminder that common multiples are the numbers that are MULTIPLES of 15 and 21. Every little bit helps.
I really like this and will use if for what is left of the school year and for our review. I always tell my students that LCM, the 'M' will help them to know that they can multiply. So when they remember LCM and multiply they will know that with GCF you will divide.
ReplyDeleteI truly like this and will use it for our review and the remaining months of the school year. I constantly tell my pupils that LCM, or the letter "M," will give them the confidence to know how to multiply. They will therefore understand that you divide with GCF when they multiply and recall LCM.
DeleteThis is great, and I'll use it throughout the rest of the school year and during our evaluation. I remind my students frequently that LCM, or the letter "M," will give them the assurance they need to be able to multiply. As a result, when students multiply and remember LCM, they will comprehend that you divide with GCF.
ReplyDeleteGCF (Greatest Common Factor) and LCM (Least Common Multiple) are mathematical concepts used in number theory and arithmetic.
ReplyDeleteGCF refers to the largest number that divides two or more integers without leaving a remainder. It is also known as the greatest common divisor (GCD). For example, the GCF of 12 and 18 is 6 because 6 is the largest number that can divide both 12 and 18 evenly.
LCM, on the other hand, refers to the smallest multiple that is evenly divisible by two or more integers. It is also known as the least common denominator. For example, the LCM of 4 and 6 is 12 because 12 is the smallest multiple that is divisible by both 4 and 6.