Division

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Division
Using multiplication and
traditional short division
What’s It All About?
You are going to learn:
How to divide by inversing multiplication and using
traditional short division.
What skills should you have already?
You need to be able to multiply and subtract two
values using a written method.
Division
Remember that 6 ÷ 3 means “how many threes make 6?”
Division is the INVERSE of Multiplication.
There are different ways of showing division.
6÷3
6
3
The answer is the same in all three cases!
3 6
Using Multiplying to Divide
For multiplying, we can use a grid like this:
2
3
4
5
6
1
2
2
4
3
6
4
8
5 6 7 8 9
10 12 14 16 18
3
4
5
6 9 12 15 18 21 24 27
8 12 16 20 24 28 32 36
10 15 20 25 30 35 40 45
6
12 18 24 30 36 42 48 54
We can now use it to divide as well as multiply.
Example: 20  4 means “How many 4’s make 20?”
The answer is 5
Your Turn
Remember that 6 ÷ 3 means “how many threes make 6?”
Work out:
1.
16 ÷ 4
2.
30 ÷ 5
3.
30 ÷ 10
4.
45 ÷ 9
5.
72 ÷ 8
6.
21 ÷ 3
7.
21 ÷ 7
Traditional Short Division 1
Find the answer to £84 ÷ 4 How many 4’s make 84?
Set up the division:
2 1
4 84
You have 8 ten pound notes
to share between 4 people.
How many do they get each?
You have 4 one pound coins
to share between 4 people.
How many do they each get?
£84 ÷ 4 = 21
Traditional Short Division 2
Work out 312 ÷ 12
How many 12’s make 312?
Set up the division:
2
12 331 2
You have 3 one hundred
pound notes to share
between 12 people.
Can you share out the
notes?
No
Change them into ten pound
notes...
This question is not about
money, but it is easier if you
think of it in that way...
You have 31 ten pound notes
to share between 12 people.
How many do they each get?
12  2 = 24 and 12  3 = 36
How many notes are left?
31 – 24 = 7
Traditional Short Division 2
Work out 312 ÷ 12
Set up the division:
2 6
12 33172
How many notes are left?
31 – 24 = 7
Change them into one pound coins.
You have 72 one pound coins
to share between 12 people.
How many do they each get?
12  6 = 72
312 ÷ 12 = 26
Traditional Short Division 3
Work out 484 ÷ 11
How many 11’s make 484?
Set up the division:
4
11 448 4
You have 4 one hundred
pound notes to share
between 11 people.
Can you share out the
notes?
No
Change them into ten pound
notes...
You have 48 ten pound notes
to share between 11 people.
How many do they each get?
11  4 = 44 and 11  5 = 55
How many notes are left?
48 – 44 = 4
Traditional Short Division 3
Work out 484 ÷ 11
How many 11’s make 484?
Set up the division:
4 4
11 44844
Change them into one pound
coins.
You have 44 one pound coins
to share between 11 people.
How many do they each get?
11  4 = 44
484 ÷ 11 = 44
How many notes are left?
48 – 44 = 4
Your Turn
Remember that 6 ÷ 3 means “how many threes make 6?”
Work out:
1.
728 ÷ 8
2.
219 ÷ 3
3.
21749 ÷ 7
4.
384 ÷ 12
5.
2190 ÷ 10
6.
273 ÷ 13
7.
2310 ÷ 11
End
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