LCM and GCF

6.NS.4

I am learning how to find the Greatest Common Factor (GCF) and Least Common Multiple (LCM) of two numbers.

Remember that we are going to list our factors to find the GCF of 2 numbers

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You can circle all the factors that are shared, but only the largest one is the Greatest Common Factor​

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​Recall what a factor is...

What is the GCF here?​

Why is only the 4 circled here?

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What is the GCF?

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Who can explain what those lines are for?​

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Multiple Choice

What does GCF mean?

• Great Cookie Fever

• Greatest Compared Factor

• Greatest Common Multiple

• Greatest Common Factor

Multiple Choice

Select the number that is a factor of 14.

• 5

• 7

• 3

• 28

Multiple Choice

What is the GCF (Greatest Common Factor) of 12 and 6?

• 1

• 6

• 2

• 3

Multiple Choice

GCF of: 
14 and 20

• 7
• 28
• 2
• 6

Multiple Choice

GCF 24 and 36

• 8
• 6
• 12
• 4

Lists are our friend when it comes to LCM as well.

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5: 5, 10, 15, 20, 25, 30

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3:​ 3, 6, 9, 12, 15, 18, 21, 24, 27, 30

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What is the LCM?​

How can I list multiples on numbers?

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What are the common multiples here​ ---------------->

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Recall what a multiple is.​

Now lets talk LCM...what is it?

Do not get confused when using lists.

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Make sure you know if you are trying to find the GCF or LCM

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​Another one...

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Multiple Choice

What is the LCM (Least Common Multiple) of 4 and 10?

• 4

• 40

• 15

• 20

Multiple Choice

Find the least common multiple (LCM) of 2 and 12.

• 2

• 4

• 6

• 12

Multiple Choice

Find the least common multiple (LCM) of 2 and 3

• 2

• 3

• 6

• 12

Multiple Choice

what is a multiple of 14

• 28
• 7
• 20
• 5

Multiple Choice

LCM stands for Least ___________ __________

• Common Multiple

• Common Multiplier

• Circular Modem

• Core Multiple

Now your turn

Some text here about the topic of discussion

I will give you the group of numbers you will list.

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For multiples, only list the first 10-12​

With a partner, you will do 2 different charts.

One ​chart will list Factors, the other will list Multiples