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Common Multiples and Least Common Multiple Mrs. Young EMC 1
Product ,[object Object],6  X  6  =  36
What is the product? 7  X  8  =  56
What is the product? 8  X  9  =  72
Multiple ,[object Object],Some multiples of 6  6, 12, 18, 24, 30, 36, 42
Name some multiples of 5 5, 10, 15, 20, 25, 30, 35
Name some multiples of 7 7, 14, 21, 28, 35, 42, 49
Name some multiples of 4 4, 8, 12, 16, 20, 24, 28
Name some multiples of 9 9, 18, 27, 36, 45, 54, 63
Common Multiple ,[object Object]
Find the least common multiple of 3 and 6 ,[object Object],[object Object],[object Object]
Step 2: ,[object Object],3:  3, 6, 9, 12, 15, 18, 21, 24 6:  6, 12, 18, 24, 30, 36, 42, 48
Step 3: ,[object Object],[object Object],3:  3,  6 , 9,  12 , 15,  18 , 21,  24 6:  6 ,  12 ,  18 ,  24 , 30, 36, 42, 48 So, the least common multiple (LCM) is 6.  Note that there is only ONE least common multiple, but there may be more than one common multiple.
Find the least common multiple of 9 and 12 Step 1:  List the multiples of both numbers (only list the first 8) 9:  9, 18, 27, 36, 45, 54, 63, 72 12:  12, 24, 36, 48, 60, 72, 84, 96
Step 2: ,[object Object],9:  9, 18, 27, 36, 45, 54, 63, 72 12:  12, 24, 36, 48, 60, 72, 84, 96
Step 3:   ,[object Object],[object Object],9:  9, 18, 27,  36 , 45, 54, 63,  72 12:  12, 24,  36 , 48, 60,  72 , 84, 96 So, the least common multiple (LCM) is 36.  Note that there is only ONE least common multiple, but there may be more than one common multiple.
Find the least common multiple of 4 and 6 ,[object Object],[object Object],[object Object]
Step 2: ,[object Object],4:  4, 8, 12, 16, 20, 24, 28, 32 6:  6, 12, 18, 24, 30, 36, 42, 48
Step 3: ,[object Object],[object Object],4:  4, 8,  12 , 16, 20,  24 , 28, 32 6:  6,  12 , 18,  24 , 30, 36, 42, 48 So, the least common multiple (LCM) is 12.  Note that there is only ONE least common multiple, but there may be more than one common multiple.

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