#### Transcript Factors_and_multiples

```What are the first five multiples of:
3, 6, 9, 12, 15
a) 3
4, 8, 12, 16, 20
b) 4
11, 22, 33, 44, 55
c) 11
21, 42, 63, 82, 105
d) 21
A multiple of a number is what you get
when you multiply that number by
some other whole number.
Multiples are
Usually
Larger
Than
Individual numbers,
Possibly
Larger never
Ever
Smaller
What are the factors of:
1, 2, 4, 8, 16
a) 16
1, 2, 5, 6, 15, 30
b) 30
1, 2, 4, 8
c) 8
1, 7
d) 7
A factor is a whole number which divides
exactly into a whole number, leaving no
remainder.
A prime number has exactly two factors:
1, and the number itself.
Factors
Are
Certainly
Tiny
Or
Really
Small
• What is the LCM of :
a) 4 and 5 20
b) 10 and 30 30
c) 12 and 15 60
• What is the HCF of :
a) 3 and 12 3
b) 30 and 56 2
c) 21 and 40 1
Go to Google, and type in ‘nrich factors and multiples game’ then click
on ‘I’m Feeling Lucky’. Scroll down the screen until you see the
interactive game and click on ‘Full Screen’.
How to play:
The first player chooses a positive even number that is less than 50, and
drags the number from the left hand grid and drops it on the right hand
grid.
The second player chooses a number to drag across. The number must
be a factor or multiple of the first number.
Players continue to take it in turns to choose numbers, at each stage
choosing a number that is a factor or multiple of the number just
chosen by the other player.
The first person who is unable to take a turn loses.
Questions
Do you have any winning strategies?
Are there any numbers you shouldn't go to?
Extension
When you have found some winning strategies and
written them in your book, change the aim of the
game:
Work in pairs trying to find the longest sequence of
numbers that can be selected. Each number can only
appear once in a sequence.
Can more than half the numbers be chosen?
```