Finding the LCM

Finding the Least Common Multiple (LCM)

Objective: Understand what Least Common Multiple is and then calculate the least common multiple.

Least- Smallest
Common- something shared
Multiple- how we "count" by a number (said number mutlipled by a whole number)

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What is Least Common Multiple?

Dropdown

List the multiples of 11:

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Select answer

, 22, 33, 44, 55, ​

Select answer

,

Select answer

Fill in the Blanks

List the multiples of 7:

7, 14, 21,

, 35, 42

Multiple Choice

Which of the following numbers is not multiple of 4?

• 12
• 8
• 16
• 26

Method #1- Listing Method

List out the first 4-5 multiples of each number and see if they have any in common. If not, list out the next 4-5 and repeat.

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How do you find the LCM

Find the LCM of 8 and 12 using the listing method.

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Method #2- Factor Tree

Create a factor tree for both of the numbers. Any primes they have in common, you take and multiply together. Any the don't have in common, you take out and multiply as well.

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How do you find the LCM

Find the LCM of 8 and 12 using the factor tree method.

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Method #3- Division Method/Birthday Cake

Do the division/birthday cake for both numbers at the same time. Once completed, circle all the outside numbers.

How do you find the LCM

Find the LCM of 8 and 12 using the division method.

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Math Response

Using any method, find the LCM of 4 and 6.

Type answer here

Correct Answer: 12

Deg^°

Rad

Math Response

Using any method, find the LCM of 9 and 3.

Type answer here

Correct Answer: 9

Deg^°

Rad

Math Response

Using any method, find the LCM of 9 and 15.

Type answer here

Correct Answer: 45

Deg^°

Rad

Math Response

Using any method, find the LCM of 10 and 12.

Type answer here

Correct Answer: 60

Deg^°

Rad

Math Response

Using any method, find the LCM of 18 and 14.

Type answer here

Correct Answer: 126

Deg^°

Rad

Poll

Which method do you think you like the best?

• Listing

• Factor Tree

• Birthday Cake/Division