Factors, Multiples and Prime Numbers

What are the factors of 20?

• 1, 2, 4, 5, 10, 20

• 1, 2, 5, 10, 20

• 1, 2, 3, 4, 10, 20

• 1, 2, 4, 5, 8, 10, 20

What are the factors of 16?

• 1

• 2

• 3

• 4

• 8

How many factors does 15 have?

• 4

• 5

• 3

• 2

What are the common factors of 12 and 18?

• 1

• 2

• 3

• 4

• 6

How many common factors are there in 8 and 14?

• 2

• 1

• none

• 3

• 4

Which of the following are multiples of 7?

• 14

• 35

• 49

• 27

• 54

What is the 8th multiple of 6?

• 48

• 54

• 56

• 46

• 42

What is the 3rd common multiple of 4 and 6?

• 36

• 32

• 30

• 28

• 24

What are the common multiples of 3 and 4?

• 12

• 18

• 24

• 32

• 36

Which of the following is a group of prime numbers?

• 2, 3, 5, and 7

• 11, 13, 17 and 19

• 1, 2, 3, and 4

• 3, 5, 7 and 9

• 13, 15, 17 and 21