Review GCF & LCM with Prime Factorization

Review
Prime Factorization, LCM, & GCF

Make sure you know the difference between a FACTOR & a MULTIPLE!

​A factor is used to multiply
A multiple is what you get when you multiply (skip counting)

Fill in the Blanks

Which factor of 27 is missing from the list? 1, 3, 27

Fill in the Blanks

Which factor of 30 is missing from the list? 1, 2, 3, 5, 6, 10, 15

Fill in the Blanks

What multiple of 5 comes next? 5, 10, 15, 20,

Fill in the Blanks

What multiple of 8 is missing? 8, 16,

, 32, 40

Match

Match the following factors and multiples.

• 1, 2, 5, 10

• 10, 20, 30, 40, ...

• 4, 8, 12, 16, ...

• 1, 2, 4

• 1, 5

Factors of 10

Multiples of 10

Multiples of 4

Factors of 4

Factors of 5

• Factors of 10

• Multiples of 10

• Multiples of 4

• Factors of 4

• Factors of 5

​Make sure you know the difference between
Prime & Composite numbers!

Multiple Choice

How many factors does a prime number have?

• Tons

• Two

• Four

• None

Dropdown

The number two has only two factors, the numbers you can multiply to get the number two. They are one and ​

Select answer

. Since there are only two ​

Select answer

of the number two, it is a ​

Select answer

number. The number four is a ​

Select answer

number since it has more than two factors. Its factors are ​

Select answer

, two, and four.

Multiple Select

Which of the following 2 are PRIME numbers?

• 19

• 21

• 22

• 23

Multiple Select

Which of the following 2 are COMPOSITE numbers?

(HInt: Use your divisibility rules!)

• 79

• 84

• 97

• 126

Multiple Choice

What is the goal of prime factorization?

• To find all even factors of a number

• To find all odd factors of a number

• To find all factors of a number that are prime

• To find all factors of a number that are composite

Multiple Choice

Which of the following shows the use of prime factorization to find the GCF?

Match

Match the following:

LCM = 84

LCM = 3,720

GCF = 6

GCF = 4

• LCM = 84

• LCM = 3,720

• GCF = 6

• GCF = 4

Fill in the Blanks

What is the LCM of 4 and 14?

Fill in the Blanks

What is the GCF of 4 and 14?

Fill in the Blanks

What is the GCF of 12, 22, and 34

Fill in the Blanks

What is the LCM of 18 and 56?