Greatest Common Factor and Prime Numbers

The video tutorial explains how to find the greatest common factor (GCF) of multiple numbers using factor trees. It begins with an introduction to the concept of GCF, followed by a step-by-step guide on creating factor trees for each number. The tutorial demonstrates how to identify common prime factors across the factor trees and multiply them to find the GCF. Two examples are provided to illustrate the process, and the video concludes with a summary of the steps involved in finding the GCF.

What is the greatest common factor (GCF)?

• The largest number that divides all given numbers

• The product of all given numbers

• The sum of all given numbers

• The smallest number that divides all given numbers

What is the first step in finding the GCF of multiple numbers?

• Subtract the smallest number from the largest

• Multiply all the numbers

• Create a factor tree for each number

• Add all the numbers together

Which of the following is a prime number?

• 4

• 9

• 6

• 3

In the example with numbers 12, 24, and 36, what is the GCF?

• 18

• 24

• 12

• 6

Which prime numbers are common in the factor trees of 12, 24, and 36?

• 2 and 3

• 3 and 5

• 3 and 7

• 2 and 5

What is the GCF of the numbers 22, 16, and 42?

• 6

• 4

• 2

• 8

Which number is not a prime factor of 42?

• 7

• 3

• 2

• 5

What is the common prime factor found in the factor trees of 22, 16, and 42?

• 2

• 3

• 5

• 7

What is the final step in finding the GCF of multiple numbers?

• Multiply the common prime factors

• Add all the prime factors together

• Divide the largest number by the smallest

• Subtract the common factors

What should you do after creating a factor tree for each number?

• Multiply all the numbers

• Add all the numbers

• Circle each prime number

• Circle each composite number