Greatest Common Factor with Prime Factors
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Objective
I can determine the greatest common factor of two numbers by using prime factorization.
Part 1 of 4
Warm-up video
Math with Mr. J · 8:11Vetted channel
We don't generate video — this one is by Math with Mr. J on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
The greatest common factor, also known as the GCF, can be found using prime factorization.
- 2
To find the GCF of two numbers using prime factorization, first find the prime factorization of both numbers, then identify the common prime factors, and finally multiply those common prime factors.
- 3
The GCF of 48 and 72 is 24 because they have three factors of 2 and one factor of 3 in common (2 x 2 x 2 x 3 = 24).
Part 3 of 4
Practice
6 questions
What is the first step in finding the greatest common factor (GCF) of two numbers using prime factorization?
Determine the prime factorization of 36 and 54. List the prime factors for each number.
Part 4 of 4
Exit ticket
Quick comprehension check
“Determine the greatest common factor (GCF) of 90 and 126 using prime factorization. Show all steps.”
Sample answer included in the free materials
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