How to Find the Least Common Multiple

Math with Mr. J

This instructional math video by Mr. J breaks down the concept of Least Common Multiple (LCM) in a clear, step-by-step format. The video begins by defining the terms "least," "common," and "multiple" to help students understand exactly what they are looking for. It then proceeds through four distinct examples, starting with simple number pairs and progressing to a more complex scenario involving three different numbers. Mr. J demonstrates the strategy of listing multiples (skip counting) for each number until a shared value is found. The content focuses on building foundational number sense skills that are critical for later operations, particularly adding and subtracting fractions with unlike denominators. Key themes include skip counting strategies, identifying commonalities between number sets, and the concept that multiples extend infinitely. The video also addresses the problem-solving strategy of extending lists when a common multiple isn't immediately apparent. For educators, this video serves as an excellent direct instruction tool or review resource for upper elementary and middle school students. It models a reliable method for finding LCM that is accessible to students who may struggle with multiplication facts, as it relies on additive skip counting. The clear visual representation of listing numbers and circling the match helps visual learners grasp the concept, making it a versatile resource for introducing the topic or remediating struggling learners.