Finding the Greatest Common Factor: Methods and Techniques

This video tutorial by Jeff Jacobson introduces the concept of the Greatest Common Factor (GCF). It explains what GCF is and demonstrates two methods to find it: listing factors and prime factorization. The tutorial uses the example of finding the GCF of 24 and 40, showing step-by-step how to list factors and use a factor tree for prime factorization. The video concludes with a summary of the methods and encourages viewers to try finding GCF on their own.

What does GCF stand for?

• Greatest Common Factor

• Greatest Common Fraction

• Greatest Common Function

• Greatest Common Formula

What is the first step in finding the GCF by listing factors?

• Subtract the numbers

• List the factors of each number

• Divide the numbers

• Multiply the numbers

Which of the following is a factor of 24?

• 5

• 7

• 8

• 9

Tags

CCSS.4.OA.B.4

Which of the following is NOT a factor of 40?

• 5

• 3

• 2

• 1

Tags

CCSS.4.OA.B.4

What is the greatest common factor of 24 and 40?

• 4

• 6

• 10

• 8

What is the first step in finding the GCF using prime factorization?

• Divide the numbers

• Multiply the numbers

• Create a factor tree

• List all factors

Which of the following is a prime factor of 24?

• 4

• 8

• 6

• 3

Tags

CCSS.4.OA.B.4

How many 2's are there in the prime factorization of 40?

• 1

• 3

• 2

• 4

Tags

CCSS.4.OA.C.5

What is the GCF of 24 and 40 using prime factorization?

• 4

• 10

• 6

• 8

What should you do after finding the common prime factors in both numbers?

• Add them

• Divide them

• Subtract them

• Multiply them