LCM Lesson & Practice

Least Common Multiple
(LCM)

I can make a table to list the multiples of two numbers and find one that is the same.

Success Criteria

I can find the least common multiple of two whole numbers less than or equal to 12.

Learning Goal

Learning Expectations

Open Ended

What do you think the word "Multiple" means in terms of multiplication?

Open Ended

What does the word "least" mean?

Open Ended

What does it mean if two people/ have something in "common"?

Important Vocabulary

• Multiples- products of a number when multiplied by 1, 2, 3, 4,

• Least- smallest, lowest

• Common- the same number that appears in both numbers.

• Least common multiple (LCM)- the smallest multiple that 2 or more numbers have in common.

Steps to find the LCM

1. Make a chart for each of your given numbers.

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​2. Take each number and multiply it by 1, 2, 3, 4, & so on- taking turns between each given number.

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3. When you find a common multiple STOP!!! This will be your least common multiple (LCM).

Least Common Multiple

LCM

Find the LCM of each set of numbers.

LCM of 9 and 12

12 =

9 =
 

Find the LCM of each set of numbers.

LCM of 9 and 12

12 = 12, 24, 36, 48, 60

9 = 9, 18, 27, 36

LCM= 36
 

Multiple Choice

LCM(3, 8) =

• 16

• 24

• 32

• 48

Multiple Choice

LCM(5, 10) =

• 50

• 30

• 10

• 5

Multiple Choice

LCM(6, 7) =

• 84

• 21

• 13

• 42

Multiple Choice

LCM(2, 8) =

• 8

• 4

• 16

• 24

Multiple Choice

LCM(12, 8)

• 96

• 24

• 36

• 72

Multiple Choice

LMC(10, 6) =

• 30

• 60

• 50

• 40

Multiple Choice

LCM(12, 6) =

• 18

• 36

• 24

• 12

Multiple Choice

LCM(6, 4)

• 24

• 12

• 8

• 10

Multiple Choice

LCM(6, 8) =

• 24

• 12

• 48

• 14

Multiple Choice

CHALLENGE QUESTION:

LCM(3, 5, 6) =

• 30

• 24

• 18

• 90