Which of these is a full list of factors of 24?
24, 48, 72, 96
1, 2, 3, 4, 6, 8, 12, 24
0, 1, 2, 3, 4, 6, 8, 12, 24
Which of these is a full list of the common factors of 12 and 30?
1, 2, 3, 4, 6
1, 2, 4, 6
1, 2, 3, 6
What is the highest common factor (HCF) of 24 and 42?
6
12
3
What is the highest common factor (HCF) of 15 and 45?
1, 3, 5, 15
5
15
What is the highest common factor (HCF) of 30, 45 and 66?
9
How many factors does the number 36 have?
7
8
Look at the following list of numbers: 2, 36, 9, 6, 24
Which number is a factor of 18 but not a multiple of 2?
36
Find the highest common factor (HCF) of 32 and 40.
4
16
Find the highest common factor (HCF) of 48, 54 and 72.
18
24
Explain why 17, 23 and 37 have no common factor (other than 1)
They are square numbers
They are not divisible by 2
They are prime numbers