Finding the Greatest Common Factor: Step-by-Step Guide

In this video, Mr. J explains how to find the greatest common factor (GCF) of two numbers. He begins by defining factors and the GCF, then provides two examples: finding the GCF of 16 and 24, and 15 and 35. For each example, he lists the factors of each number, identifies the common factors, and determines the greatest one. The video concludes with a summary of the process.

What is the greatest common factor (GCF)?

• The sum of all factors of two numbers

• The largest factor that two numbers share

• The smallest factor that two numbers share

• The product of all factors of two numbers

Which of the following is a factor of 16?

• 3

• 9

• 5

• 8

What is the product of the factors 2 and 8 for the number 16?

• 18

• 16

• 14

• 10

Which of the following is NOT a factor of 24?

• 6

• 5

• 3

• 12

What is the greatest common factor (GCF) of 16 and 24?

• 8

• 6

• 4

• 2

Which of the following is a factor of 15?

• 3

• 6

• 2

• 4

What is the product of the factors 3 and 5 for the number 15?

• 10

• 8

• 15

• 20

Which of the following is NOT a factor of 35?

• 10

• 35

• 7

• 5

What is the greatest common factor (GCF) of 15 and 35?

• 3

• 5

• 7

• 15

Which of the following pairs of numbers share the greatest common factor of 5?

• 25 and 35

• 15 and 25

• 20 and 30

• 10 and 20