Factors Multiples and Prime and Lcm and Gcf

Which of the following is NOT true about prime numbers? 

• They have exactly two factors 

• 1 is a factor of every prime number

• No prime numbers end in zero

• All prime numbers are odd numbers.  

A prime number

• has one factor

• has more than 2 factors

• has exactly 2 factors: 1 and the number itself

Use a factor tree to find the prime factorisation of 168

Find the prime factorization of 18

• 2 • 9

• 2² • 3

• 2 • 3²

• 3 • 6

Find the prime factorization of 60

• 5 • 12

• 2 • 3² • 5

• 2² • 3 • 5

• 2⁷

Find the prime factorization of 30

• 2² • 5 • 7

• 2 • 3²

• 2 • 3 • 7

• 2 • 3 • 5

Find the prime factorization of 81

• 2² • 7

• 2³ • 5 • 7

• 4³

• 3⁴

Find the GCF of 64 and 144

• 8

• 6

• 16

• 2

What is the GCF of 18 and 24?

• 3

• 6

• 8

• 9

What is the GCF of 4 and 12?

• 3

• 1

• 6

• 4