Factors and multiples

Which of the following numbers is a common factor of 15 and 25? a) 3 b) 5 c) 7 d) 9

• b) 5

• d) 9

• c) 7

• a) 3

What we can multiply to get a certain number. 5 and 2 are ____________ of 10. 

• multiple
• inverse operation
• factor
• divisor

18 and 36 both have ____ as a factor.

• 4

• 6

• 12

• 36

Which has a factor of 7?

• 19

• 1

• 21

• 67

Common factors of 9 and 15 are

• 1

• 3

• 9

• 15

1, 2, 3, 6, 9, 18 are all factors of 18.

• True

• False

24, 32, 64 and 72 are...

• factors of 2

• multiples of 2

• factors of 72

• multiples of 8

How would you increase a number by a factor of 5?

• add 5
• subtract 5
• multiply by 5
• divide by 5

Richard is thinking of a secret number. He tells his brother that it is divisible by 9 and tells his friend that it is divisible by 3. If Richard is telling the truth to both of them, what is the smallest secret number that Richard could be thinking of?

• LCM

• GCF

• 3

• 9

The numbers 12, 24, 36 are

• factors of 12

• multiples of 12