pdf Using Factor Trees To Find The LCM

Tagged in 4.OA.B.4, 6.NS, 6.NS.B.4, 6th grade, factor trees, factors and multiples, lcm, least common multiple, math practice, number theory, prime factorization, whole numbers

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Using Factor Trees To Find The LCM

This worksheet teaches students how to find the least common multiple (LCM) using prime factorization and factor trees, emphasizing conceptual understanding over memorization. Students build factor trees for each number, identify matching prime factors, and then focus on the uncircled primes to correctly determine the LCM. This method helps clarify a common misconception by reinforcing that LCM depends on what is not shared, rather than what is paired.

Step-by-step directions and worked examples guide students through the entire process, making this resource effective for direct instruction, guided practice, or review when introducing LCM with prime factorization.

Skills Assessed

  • Building factor trees using prime factorization

  • Identifying prime factors of whole numbers

  • Finding the least common multiple of two numbers

  • Analyzing shared vs. unshared prime factors

  • Applying structured reasoning to number relationships

Details

  • Pages: 4

  • Problems: 10

  • Answer Key: Included

ID# 0244