Download Factors, Multiples and Primes : Foundation

Factors, Multiples and Primes :
Which grade are you…..?
Foundation
2 Here is a list of numbers.
90, 108, 210, 306, 495, 501
Grade G
1 Write down all of the factors of 18.
Which of the numbers in the list are multiples of 5
3 Here is a list of numbers
a) Which of the numbers are prime numbers?
Grade E
2, 3, 4, 6, 9, 11, 12, 15, 17, 18
b) Which of the numbers are square numbers?
c) Which of the numbers has the most factors?
Show how you decide.
b) What is the highest common factor of 24 and 56
Grade D
4 a) List the factors of 24
5 Find the lowest common multiple of 12 and 20.
7 The highest common factor of two numbers is 8.
Give three possible pairs of numbers.
8 Ben says that if you write 40 as a product of primes the answer is
1 × 23 × 5
Is he correct?
Explain your answer.
www.mathsbox.org.uk
Grade C
6 Express 120 as a product of primes
Factors, Multiples and Primes :
Which grade are you…..?
Answers
Foundation
2 Here is a list of numbers.
90, 108, 210, 306, 495, 501
Grade G
1 Write down all of the factors of 18. 1, 2, 3, 6, 9, 18 
Which of the numbers in the list are multiples of 5? 90, 210, 495 
3 Here is a list of numbers
a) Which of the numbers are prime numbers? 2, 3, 11, 17 
b) Which of the numbers are square numbers? 4, 9 
Grade E
2, 3, 4, 6, 9, 11, 12, 15, 17, 18
c) Which of the numbers has the most factors? 12 
Show how you decide. 
1, 2, 3, 4, 6, 8, 12, 24 
b) What is the highest common factor of 24 and 56 8 
Grade D
4 a) List the factors of 24
5 Find the lowest common multiple of 12 and 20. 60 
7 The highest common factor of two numbers is 8.
Give three possible pairs of numbers. 
8 Ben says that if you write 40 as a product of primes the answer is
1 × 23 × 5
Is he correct? No 
Explain your answer. 1 is not a prime number 
www.mathsbox.org.uk
Grade C
6 Express 120 as a product of primes 23 × 3 × 5 (2 x 2 x 2 x 3 x 5) 