prime number – an integer whose only factors are 1 and itself 2, 3, 5, 7,11, 13, 17, 19
TRANSCRIPT
Prime Factor Tree for 60
Write 60 at the top of the page 60
60 = prime number 2 x 30 2
2
30
15
3 5
30 = prime number 2 x 15
15 = prime number 3 x prime number 5
60 is all the prime numbers 2 x 2 x 3 x 5 multiplied together
1. 30 and 45
2. 45 and 20
3. 40 and 80
4. 36 and 24
5. 32 and 16
HCF = 15
HCF = 5
HCF = 40
HCF = 11
HCF = 16
Multiple of 5 5, 10, 15, 20, 25, 30 ....Multiple of 88, 16, 24, 32, 40, 48 .....Multiple of 4242, 84, 126, 168, 210 ...
Find the lowest common multiple of 4 and 18
4, 8, 12, 16, 20, 24, 28, 32, 36, 40…….
18, 36, 54, 72…….
LCM = 36
Find the Lowest Common Multiple
1. 15 and 6
2. 9 and 12
3. 24 and 6
4. 4 and 18
5. 15 and 16
LCM = 30
LCM = 36
LCM = 24
LCM = 36
LCM = 240
2460
Venn Diagram24 = 2 x 2 x 2 x 3
60 = 2 x 2 x 3 x 5
22
3
2 5
HCF = 2 x 2 x 3 = 12
LCM = 2 x 2 x 2 x 3 x 5 = 120
HCF is the region of
intersection2 x 2 x 3 = 12
LCM is all the numbers in the circles
multiplied together 2 x 2 x 2 x 3 x 5=120
Find the HCF and LCM of the following:
1. 6 and 15
2. 20 and 30
3. 14 and 42
4. 24, 30 and 54Answers:
1.HCF = 3, LCM = 30
2.HCF = 10, LCM = 60
3.HCF = 14, LCM = 42
4.HCF = 6, LCM = 1080