Find the GCF and LCM using prime factorization

This video tutorial explains how to find the greatest common factor (GCF) and least common multiple (LCM) of two whole numbers using their prime factors. It covers the concepts of prime and composite numbers, demonstrates the use of factor trees for prime factorization, and clarifies common misunderstandings between factors and multiples. The tutorial provides step-by-step examples of finding the GCF and LCM for the numbers 8 and 30, as well as 18 and 27, using Venn diagrams to compare prime factors.

What is a prime number?

• A number with exactly two factors

• A number with only one factor

• A number with more than two factors

• A number that is a multiple of 10

Which of the following is a composite number?

• 10

• 5

• 3

• 2

How do you find the GCF of two numbers using their prime factors?

• By subtracting the prime factors

• By identifying the shared prime factors

• By multiplying all the prime factors

• By adding all the prime factors

What is the LCM of 8 and 30?

• 30

• 240

• 120

• 60

What is the GCF of 18 and 27?

• 3

• 12

• 6

• 9