round whole numbers to the nearest 10 or 100. learning objective revise chunking

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Round whole numbers to the nearest 10 or 100.

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Page 1: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Round whole numbers to the nearest 10 or 100.

Page 2: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Learning Objective

Revise Chunking

Page 3: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

72 ÷ 4 =

4 72we know 10 x 4 40

32we know 8 x 4 32

0

18

18

We highlight the times table we are using.

We circle the number of groups.

Page 4: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

84 ÷ 6 =

6 84we know 10 x 6 60

24we know 4 x 6 24

0

14

14

We highlight the times table we are using.

We circle the number of groups.

Page 5: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Try this one on your whiteboard…

96 ÷ 6 =

96

6

we know 10 x 6 60

36we know 6 x 6 36

0

16

16

Page 6: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Try this one on your whiteboard…

112 ÷ 8 =

1128

we know 10 x 8 80

32we know 4 x 8 32

0

14

14

Page 7: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Try this one on your whiteboard…

108 ÷ 6 =

1086

we know 10 x 6 60

48we know 8 x 6 48

0

18

18

Page 8: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Try this one on your whiteboard…

125 ÷ 5 =

1255

we know 10 x 5 50

75we know 10 x 5 50

25

25

25

we know 5 x 5 25

0

Page 9: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Learning Objective

Revise Chunking

Page 10: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

PROBLEM!

78 children will be placed in teams of 6.

How many teams will there be?

Q. What calculation do we need to solve this problem?

When you have decided how to do it work out the answer.

Page 11: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

We need to do the division sum 78 ÷ 6.

We can do this by chunking…78

- 60 ( 10 x 6 )18

- 18 ( 3 x 6 ) 0

Q. How many 6’s have been subtracted?

78 ÷ 6 = 13

Page 12: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Q. What would be the answer if there had been 80 children?

Page 13: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Using chunking….

80 - 60 (10 x 6 )

20 - 18 ( 3 x 6 )

2 13 r.2

Using pencil and paper we write… 80 ÷ 6 = 13 remainder 2

Page 14: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Try this one with a partner

There are 85 sweets to be shared equally among 7 children.

How many sweets does each child have? How many are left?

Page 15: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Using chunking…

85 -70 (10 x 7)

15 - 14 ( 2 x 7)

1 12 r.1

Using pencil and paper…85 ÷ 7 = 12 r.1

Page 16: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

175 ÷ 7

In pairs discuss how you could calculate an answer to this.

Page 17: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Using chunking…175- 70 (10 x 7)105- 70 (10 x 7) 35- 35 ( 5 x 7) 0 Answer = 25

Page 18: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Try these:

134 ÷ 5

157 ÷ 6

119 ÷ 5

Page 19: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Q. What is

a quick way to check

whether the answer to

a division

is

correct?

Page 20: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

To check whether the answer to a

division is correct we can use the

INVERSE operation.

Page 21: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

LOOK…

57 ÷ 3 = 19

Q. Which two numbers should we

multiply to check whether this

is correct?

Page 22: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

57 ÷ 3 = 19

To use the inverse operation

we should multiply 19 by 3.

19 x 3 = 57

Page 23: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

OMA

Revise Bus Stop

Method of Division

Page 24: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Learning Objective

Express a quotient as a fraction, or as a

decimal rounded to one decimal place.

Page 25: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Mentally divide the following …

Page 26: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

The purpose of the lesson is to consider divisions that do not always have whole number answers.

Page 27: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

46/7=

Look at this as a multiplication!How many sevens make 46?

Page 28: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking
Page 29: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking
Page 30: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking
Page 31: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking
Page 32: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

1.Find the closest multiple below the number.

2.How many 7s make this multiple?

3.Calculate how many sevenths to get from the closest multiple to your number.

YOUR TASK!

Page 33: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Revise Bus Stop

Method of Division

Page 34: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

Learning Objective

Express a quotient as a fraction, or as a

decimal rounded to one decimal place.

Page 35: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking
Page 36: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking
Page 37: Round whole numbers to the nearest 10 or 100. Learning Objective Revise Chunking

HOW CAN WE WRITE THIS AS A DECIMAL?

What other easy divisors are there?