Using multiplication and written methods

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DivisionUsing multiplication and written methods

Remember that 6 ÷ 3 means “how many threes make 6?”Division is the INVERSE of Multiplication(This means it reverses multiplication)There are different ways of showing division.

6 ÷ 3

The answer is the same in all three cases!

63 3 6

Division


1 2 3 4 5 6 7 8 91 1 2 3 4 5 6 7 8 92 2 4 6 8 1

012

14

16

18

3 3 6 9 12

15

18

21

24

27

4 4 8 12

16

20

24

28

32

36

5 5 10

15

20

25

30

35

40

45

6 6 12

18

24

30

36

42

48

54

7 7 14

21

28

35

42

49

56

63

8 8 16

24

32

40

48

56

64

72

9 9 18

27

36

45

54

63

72

81

For multiplying, we use this grid:

We can now use it to divide as well as multiply!!! Example 20 4 means How many 4’s make 20?

Using Multiplying to Divide

The answer is 5 !!

Find 20 in the fours row ....

5 fours make 20 so....


1 2 3 4 5 6 7 8 91 1 2 3 4 5 6 7 8 92 2 4 6 8 1

012

14

16

18

3 3 6 9 12

15

18

21

24

27

4 4 8 12

16

20

24

28

32

36

5 5 10

15

20

25

30

35

40

45

6 6 12

18

24

30

36

42

48

54

7 7 14

21

28

35

42

49

56

63

8 8 16

24

32

40

48

56

64

72

9 9 18

27

36

45

54

63

72

81

For multiplying, we use this grid:

We can now use it to divide as well as multiply!!! Example 20 4 means How many 4’s make 20?

Using Multiplying to Divide

The answer is still 5 !!

Or find 20 in the fours column ....


Remember that 6 ÷ 3 means “how many threes make 6?”Use the grid to work out:16 ÷ 430 ÷ 518 ÷ 245 ÷ 972 ÷ 821 ÷ 321 ÷ 7

1 2 3 4 5 6 7 8 91 1 2 3 4 5 6 7 8 9

2 2 4 6 8 10

12

14

16

18

3 3 6 9 12

15

18

21

24

27

4 4 8 12

16

20

24

28

32

36

5 5 10

15

20

25

30

35

40

45

6 6 12

18

24

30

36

42

48

54

7 7 14

21

28

35

42

49

56

63

8 8 16

24

32

40

48

56

64

72

9 9 18

27

36

45

54

63

72

81

Your Turn

= 4= 6= 9= 5= 9= 7= 3


Bigger Numbers What about bigger numbers that are not in a multiplication grid?

There are various methods you can use.

Find one you like and stick to it!

Here are some of the more common ones:



Work out £192 ÷ 6Set up the method:

6 192 60

132 60 10

72 60 10 12

Multiply 6 by eg 10, then subtract10

Repeated Subtraction

2

32

120

Repeat this method until your green number is 0 or a number less than 6.

Total the last column

= 32

There is no “wrong” number to multiply by – but it will be

quicker if you choose wisely!


Work out £128 ÷ 8Set up the method: 8 128 80

48 48

Multiply 8 by something easy such as 10, then subtract

10

Repeated Subtraction

16

6 0

Repeat this method until your green number is 0 or a number less than 8.

= 16


If you know your tables, you can split the number up into useful parts:Work out 654 6Remember 6 6 = 1

60 6 = 10600 6 = 100

Use this split 600

Partitioning

6 is in the 6 times table and so is 54.

54 654 6 = 109

6 = 100 6 = 9


PartitioningWork out 924 4

Use this split: 800 4 = 200 120 4 = 30 4 4 = 1 924 4 = 231

9 is not in the 4 times table , but 8

is...


Find the answer to £84 ÷ 4Set up the division:

Think of this as 8 tens to sharebetween 4 people. How many do they get each?

4 8 42

Traditional Short Division

4 “ones” to be shared between 4 people.How many do they each get?

1

= 21


Find the answer to 468 ÷ 9Set up the division:

You cannot share 4 hundreds between 9, so change them to tens and carry 46 tens can be shared between 9

-› 5 with 1 left over -> change the 1 ten to units and carry across

9 4 6 84 5

1



Find the answer to 468 ÷ 9Set up the division:

How many 9’s make 18?

9 4 6 84 5

1


2

= 52

Work out:164 ÷ 4315 ÷ 153040 ÷ 10459 ÷ 9156 ÷ 12315 ÷ 57540 ÷ 10204 ÷ 17

Your Turn Pause while you have a go at

these ....= 41= 21= 304= 51= 13= 63= 754= 12

Ready...?



Work out:728 ÷ 8219 ÷ 3749 ÷ 7378 ÷ 92190 ÷ 10240 ÷ 16231 ÷ 11

More practice

= 91= 73= 107= 63= 219= 15= 21

Pause while you have a go at

these ....

Ready...?

The End


Ciao for now…

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Using multiplication and written methods