Least Common Multiple 
     Least Common Multiple 
             (LCM)
             (LCM)
  Essential Question:
  Essential Question:
  How do I find the least common 
  How do I find the least common 
   multiple of two or three numbers, 
   multiple of two or three numbers, 
   and why is this relevant to me?
   and why is this relevant to me?
  Common Core Objective:
  Common Core Objective:
  5.NS.4
  5.NS.4
  Common Core Objective:
  Common Core Objective:
  Students will be able to identify the least 
  Students will be able to identify the least 
   common multiple of two or three one, two, 
   common multiple of two or three one, two, 
   and three digit numbers with 80% accuracy.
   and three digit numbers with 80% accuracy.
    Least Common Multiple 
     Least Common Multiple 
             (LCM)
             (LCM)
  Vocabulary:
   Multiple – a non-zero .
   Least Common Multiple – the least non-
   zero common multiple of two or more 
   numbers.
         Least Common Multiple 
          Least Common Multiple 
                            (LCM)
                            (LCM)
       When thinking about finding the 
       When thinking about finding the 
          Least Common Multiple, or the 
          Least Common Multiple, or the 
                               LCM…
                               LCM…
                         REMEMBER
                          REMEMBER
          L…The smallest number
             …The smallest number
          L
          C…all terms in common
              …all terms in common
          C
          M…from their list of multiples
              …from their list of multiples
          M
    Least Common Multiple 
    Least Common Multiple 
            (LCM)
            (LCM)
   Important to Remember…
   Important to Remember…
   There are TWO methods for 
   There are      methods for 
          TWO 
    finding the Common Multiples of 
    finding the Common Multiples of 
       two or more numbers…
       two or more numbers…
     Method 1…Use Multiple Lists
     Method 1…Use Multiple Lists
   Method 2…Use Prime Factorization
   Method 2…Use Prime Factorization
      Least Common Multiple 
      Least Common Multiple 
                (LCM)
                 (LCM)
  Finding the LCM: Method 1 – Multiple List
  Finding the LCM: Method 1 – Multiple List
  Example 1: Find the LCM of 4 and 9.
  Example 1: Find the LCM of 4 and 9.
  Step 1: Create a list of multiples for each 
  number
  Step 2: Circle the first multiple the numbers have in 
  common
   4: 4, 8, 12, 16, 20, 24, 28, 32, 
   4: 4, 8, 12, 16, 20, 24, 28, 32, 
   36, 40, …
   36, 40, …
   9: 9, 18, 27, 36, 45, 54, 63,…
   9: 9, 18, 27, 36, 45, 54, 63,…
                 The LCM of 4 and 9 is 
                 36