Prime Number Factor Trees and Gcf

Use a factor tree to find prime factorization of 24.

• 2 x 3 x 2 x 3

• 2 x 3 x 2 x 2

• 6 x 2 x 2

• 2 x 3 x 4

Use a factor tree to find the prime factorization of 50.

• 2 x 2 x 5 x 5

• 5 x 5 x 3 x 2

• 2 x 5 x 5

• 2 x 25

Which of the following numbers is prime?

• 15

• 18

• 19

• 21

Which of the following is NOT prime?

• 11

• 13

• 19

• 21

Use a factor tree to find the prime factorization of 54.

• 3 x 3 x 2

• 3 x 3 x 3 x 2

• 3 x 2 x 1 x 3

• 3 x 3 x 1 x 5

Use a factor tree to find the prime factorization of 60.

• 2 x 3 x 3 x 2

• 2 x 2 x 2 x 3

• 2 x 5 x 2 x 2

• 2 x 3 x 2 x 5

Use a factor tree to find the prime factorization of 45

• 2 x 3 x 5

• 3 x 5 x 4

• 3 x 2 x 8

• 9 x 5

Prime numbers have _____ factors.

• no
• 3
• 1
• 2

Composite numbers:

• Are always bigger than prime numbers
• Have more than 2 factors
• Have 2 pairs of factors
• Don't have factors

Which number is composite?

• 11

• 13

• 21

• 23