1. Number
Factors and Multiples
Saturday, 09 September 2006
©RSH

2. Notes Factors Any number which divides exactly into 6 is a factor of 6
The factors of 6 are: 1, 2, 3, 6
Multiples
Any number in the 6-times table is a multiple of 6
The first 4 multiples of 6 are: 6, 12, 18, 24
Saturday, 09 September 2006
©RSH

3. Exercise 1. Write down the factors of 8 15 18 21 40 1, 8, 2, 4
1, 15, 3, 5
1, 18, 2, 9, 3, 6
1, 21, 3, 7
1, 40, 2, 20, 4, 10, 5, 8
2. Write down the first 4 multiples of 8 5
8, 16, 24, 32
5, 10, 15, 20
Saturday, 09 September 2006
©RSH

4. The LCM is the smallest number that both 4 and 5 divide into.
Notes
LCM (Lowest Common Multiple)
The first few multiples of 4 are: 4, 8, 12, 16, 20, 24, 28, …
The first few multiples of 5 are: 5, 10, 15, 20, 25, 30, …
The LCM of 4 and 5 is the smallest number in both lists.
The LCM of 4 and 5 is 20.
The LCM is the smallest number that both 4 and 5 divide into.
Saturday, 09 September 2006
©RSH

5. Exercise 1. Find the LCM of 2 and 5 4 and 12 6 and 9 4 and 6 8 and 1210 12 18 24
Saturday, 09 September 2006
©RSH

6. The HCF is the highest factor of both 12 and 20.
Notes
HCF (Highest Common Factor)
The factors of 12 are: 1, 2, 3, 4, 6, 12
The factors of 20 are: 1, 2, 4, 5, 10, 20
The HCF of 12 and 20 is the highest number in both lists.
The HCF of 12 and 20 is 4.
The HCF is the highest factor of both 12 and 20.
Saturday, 09 September 2006
©RSH

7. Exercise 1. Find the HCF of 12 and 18 22 and 33 6 and 9 24 and 3611 3 12
Saturday, 09 September 2006
©RSH