Greatest Common Factor
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Objective
I can use find the greatest common factor of two numbers and use the GCF to solve word problems.
Part 1 of 3
Key concepts
3 concepts
- 1
The greatest common factor (GCF) is the largest positive integer that divides two or more given integers without leaving a remainder.
- 2
To find the GCF using prime factorization, you express each number as a product of its prime factors and then multiply the lowest power of each common prime factor.
- 3
The GCF is invaluable in word problems when you need to divide distinct quantities into the largest possible equal parts, like making identical groups from different items.
Part 2 of 3
Practice
5 questions
Define the greatest common factor (GCF) in your own words.
Find the greatest common factor of 90 and 120.
Part 3 of 3
Exit ticket
Quick comprehension check
“A school is preparing for an event and has 60 blue balloons and 90 yellow balloons. They want to create identical balloon arrangements for each table, using all the balloons and maximizing the number of balloons per arrangement. Find the greatest common factor (GCF) of 60 and 90. Then, determine how many identical balloon arrangements can be made and how many blue and yellow balloons will be in each arrangement.”
Sample answer included in the free materials
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