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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
Workbook answers
1 Numbers to 100
Exercise 1.1
Challenge
Focus
10 See the grey numbers in the grid. The black
numbers refer to question 11.
1
23 = 20 + 3
49 = 40 + 9
2
21, 22, 23, 24, 25, 26, 27, 28, 29, 30
24
51, 52, 53, 54, 55, 56, 57, 58, 59, 60
3
37
3, 13, 23, 33, 43, 53, 63, 73, 83, 93
42
6, 16, 26, 36, 46, 56, 66, 76, 86, 96
24, 38
5
Learner’s own answers.
46
48
53
10, 20, 30, 40, 50, 60, 70, 80, 90, 100
4
28
69
75
81 82
84
90
Practice
6
98 = 90 + 8
73 = 70 + 3
11 Learners have added 24, 28, 42, 48, 82 and 84
to the 100 square. See the black numbers in
the grid in the answer for question 10.
71, 72, 73, 74, 75, 76, 77, 78, 79, 80
Exercise 1.2
11, 12, 13, 14, 15, 16, 17, 18, 19, 20
Focus
4, 14, 24, 34, 44, 54, 64, 74, 84, 94
1
85 = 80 + 5
7
8
9
1 ten →
10
8, 18, 28, 38, 48, 58, 68, 78, 88, 98
2 tens →
20
Learner’s own representations of 23 as 2 tens
and 3 ones, and 32 as 3 tens and 2 ones.
3 tens →
30
4 tens →
40
5 tens →
50
6 tens →
60
7 tens →
70
8 tens →
80
9 tens →
90
10 tens →
100
27
23
33
57 58 59
43 44
67
47
74
77
78
84
87
87 88 89
94 95 96 97
1
36 37 38
98
2
90 (or 9 tens)
3
50 (or 5 tens)
4
a
75: 70, 5
c
40: 40, 0
b
39: 30, 9
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
5
Estimate 50 or 100. Count 53.
6
24, 36, 42, 78, 12
10 Learner ticks 1st leaf, underlines 4th leaf and
rings 8th leaf.
Practice
11 Start/Begin at 78. Count back in twos.
Stop at 70.
7
100, 90, 80, 70, 60, 50, 40, 30, 20, 10
12 36 is smaller than 63.
8
Marcus 5 and 8, Arun 3 and 7.
13 19, 46, 57, 64, 75
9
Estimate 50 or 100. Count 67.
Challenge
10 An even number of objects can be sorted into
2 equal groups.
2 more than an odd number is always an
odd number.
Challenge
11 Large dots: estimate 20 or 50; count 21.
Small dots: estimate 50 or 100; count 48.
12 For example, an L shape. Learners may have
other ideas.
16 Learner’s own answer and matching
description.
17 84, 82, 48, 42, 28
2 Geometry
Focus
Focus
Learner will have marked the number line
with 15 halfway between 10 and 20, 43
approximately a quarter of the way between
40 and 50 and 78 approximately three-quarters
of the way between 70 and 80.
15
15 52nd and 53rd
Exercise 2.1
Exercise 1.3
1
14 54 and 87. Accept 53, 86 or 88.
43
1
b
Box: cuboid, 6 faces, 12 edges, 8 vertices,
0 curved surfaces.
0 10 20 30 40 50 60 70 80 90 100
Learner will have ringed the 3rd elephant.
3
32nd
4
42, 52, 62, 72
5
32, 34, 36, 38
6
even, ones
7
53 is greater than 35.
8
12, 21, 35, 53
Practice
9
Ball: sphere, 0 faces, 0 edges, 0 vertices,
1 curved surface.
Tin can: cylinder, 2 faces, 2 edges,
0 vertices, 1 curved surface.
78
2
aThis shape is a cube. It has 6 faces.
It has 12 edges. It has 8 vertices.
Square-based pyramid: 5 faces, 8 edges,
5 vertices, 0 curved surfaces.
2
cuboid, sphere, cylinder, cube, square-based
pyramid
3
Any 2D shape that is flat and cannot be
picked up: for example, shapes in pictures,
on wallpaper, on an item of clothing, on a
floor or wall tile.
Any 3D shape that can be picked up and
can include a can of beans, a cereal box,
a cupboard, a ball, a box.
Learner marks 3 about a quarter of the way
between 0 and 10 and 49 just before 50.
3
49
0 10 20 30 40 50 60 70 80 90 100
2
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
4
Shape
Faces
Edges Curved
surfaces
Sphere
0
0
1
0
Cylinder
2
2
1
0
Squarebased
pyramid
5
8
0
5
Cube
6
12
0
8
Cuboid
6
12
0
8
Shapes
Vertices
What is
the same?
What is different?
Square- Both have
based
vertices
pyramid and at least
1 square
Cube
face.
The square-based
pyramid has
1 square face and
5 vertices.
Practice
11 Outside the circle: sphere, cylinder. Inside the
circle: cube, pyramid, cuboid.
5
The shape could be a cube, cuboid or squarebased pyramid.
12
6
aA sphere, B cylinder, C square-based
pyramid, D cube, E cuboid
b
square-based pyramid
c
cube
7
Inside the circle is a sphere and a cylinder.
The other 3D shapes are outside the circle.
8
3D shapes can include a can of beans, a cereal
box, a cupboard, a ball, a box.
3D shape
The 2D shapes will be the faces of the
3D shapes. For example, a can of beans has
2 circular faces; a cereal box has
6 rectangular faces.
Challenge
9
Max is wrong because a square-based pyramid
has 8 edges.
10
Shapes
Cube
Cuboid
What is
the same?
What is different?
Both have
6 faces,
12 edges
and
8 vertices.
The cube has
square faces.
2D shape
This cuboid has
2 square faces and
4 rectangle faces.
Cylinder Both have The cylinder has
Sphere a curved
2 circular faces; the
surface and sphere does not.
no vertices.
3
The cube has
6 square faces and
8 vertices.
Name
Picture
2D shapes
I can see
Sphere
Circle
Cube
6 squares
Cuboid
2 squares
and 4
rectangles
Squarebased
pyramid
4 triangles
and 1
square
Name
Picture
3D shapes
I can make
Circle
Sphere,
cylinder
Square
Cube,
cuboid
Rectangle
Cuboid
Triangle
Trianglebased
pyramid
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
Exercise 2.2
4
Focus
1
Learner draws lines of symmetry on
each shape.
2
Rectangle, hexagon, octagon, pentagon.
Learner’s own answers for shape descriptions.
For example, a rectangle has 4 sides and
4 vertices. A hexagon has 6 sides and 6 vertices.
Challenge
5
Learner draws as many lines of symmetry on
each shape as they can see. E.g.:
Practice
3
4
Ladybird, star, rocket and tree are all
symmetrical. The ladybird and tree have
vertical lines of symmetry. The rocket has a
horizontal line of symmetry. The star has a
vertical and a horizontal line of symmetry.
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
3
The learner colours in a quarter of each of
the items. Learner’s own drawings of things
you can cut in quarters with one quarter of
each coloured.
4
Learner’s own answer.
Practice
6
Learner’s completed face should also be
coloured symmetrically.
5
Exercise 2.3
Focus
1
2
Half of each of the fruits are coloured in
by the learner. Learner’s own drawings of
things you can cut in half with one half of
each coloured.
Half: 6 coloured squares
Whole: 12 coloured squares
1 1
+ = 1 whole
2 2
5
6
The circle, cross and diamond show quarters
and learners will colour one quarter of those.
7
Each shape should have a different
quarter coloured.
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
Challenge
8
5 whole biscuits
9
a
1
4
c
1
2
10 9 centimetres; 5 centimetres; 11 centimetres;
4 centimetres; 13 centimetres
b
three-quarters
11 a30 centimetres, 39 centimetres,
50 centimetres, 70 centimetres
10 Learner’s own answers. The answer should
always be 2 squares as a quarter of 8 is 2.
77 centimetres, 78 centimetres,
87 centimetres, 88 centimetres
c
1
metre, 1 metre, 3 metres, 4 metres
2
11 a
1
4
b
three-quarters
12 Learner’s own answers.
c
1
2
d
1
2
Exercise 3.2
3 Measures
Focus
1
Exercise 3.1
a
8 centimetres
b
2 centimetres
c
13 centimetres
d
7 centimetres
e
11 centimetres
Focus
2
1
The answers will be different if the length of
each object is different.
Practice
2
Learner’s own answer.
3
For example: Longer: a frying pan; a table; a
skipping rope.
4
Learner’s own answers.
3
a, b Answers depend on the location.
4
Learner’s own answers.
5
Shorter: a straw; your shoe; your hand; a fork.
aA pencil case centimetres; a bus metres;
a pencil centimetres; a wall metres;
a book centimetres; a car metres.
About the same: a paint brush.
b
But these depend on the learners.
Learner’s own answer.
Learner’s own answers.
Challenge
6
A is longer. It is 3 centimetres longer than B.
Practice
7
A is shorter. It is 3 centimetres shorter than B.
5
8
B is shorter. It is 3 centimetres shorter than A.
9
A is longer. It is 14 centimetres long. The
shorter line is 13 centimetres long. The longer
line is 1 centimetre longer.
6
7
Answers will depend on the length/height of
the learner. The answers are different because
each object is a different length. They are nonstandard measures.
The pen is 9 centimetres long. Learner’s own
answers for objects that are longer and shorter
than the pen.
Metres: swimming pool; bus.
8
Learner’s own answer.
Challenge
9
Learner’s own answer.
10 a
7 centimetres
c
7 centimetres
11 a
Centimetres: bar of chocolate; shoe; 5 paper
clips joined together; worm.
6
b
b
6 centimetres
apple 10 centimetres
b
strawberry about 5 centimetres
c
pencil 20 centimetres
d
tree 5 metres
e
plaster 5 centimetres
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
7
4 Statistics
Focus
Not 2 or fewer legs
Learners should have completed the table with
the results from their 12 spins. It is unlikely
that they will have landed on each number
twice, so their experiment should have shown
that Arun is not correct.
2
Triangle
Not triangle
Striped
5 Working with
numbers to 100
Exercise 5.1
Focus
Not striped
1
7, 6
2
Learner’s own arrangements of 5 counters.
3
a
25 + 4 = 29
b
42 + 5 = 47
c
51 + 7 = 58
d
33 + 6 = 39
a
28 + 10 = 38
b
32 + 10 = 42
12
c
54 +20 = 74
d
41 + 20 = 61
9
5  35
+ 20
5
  55
b
6 + 5 + 4 = 15
6 + 4 = 10
10 + 5 = 15
b
31 + 8 = 39
Practice
3
Starfish tally chart
Starfish
Tally
Number
6
14
4
6
4
a
5 + 5 + 5 = 15
5 + 5 = 10
10 + 5 = 15
c
8 + 4 + 2 = 14
8 + 2 = 10
10 + 4 = 14
17
4
4th week 29 bikes. 1st week 16 bikes. 2nd and
3rd weeks 42 bikes.
Practice
7
87 bikes altogether.
5
2D shape
Not a 2D shape
Spots
8
No spots
9
Challenge
6
7
Cannot fly
2 or fewer legs
Exercise 4.1
1
Can fly
a
64 + 5 = 69
c  84
+ 3
d  92
+ 6
  87
  98
a
b
89 + 10 = 99
26 + 20 = 46
c  68
+ 20
d  77
+ 10
  88
  87
18 + 2 = 20
8 + 12 = 20
80 + 20 = 100
Answer depends on the learner’s spins.
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
Exercise 5.2
10 0 + 6 = 6  0 + 60 = 60
1+5=6
10 + 50 = 60
Focus
2+4=6
20 + 40 = 60
1
3+3=6
30 + 30 = 60
39 − 8 = 31
b
48 − 5 = 43
c
77 − 5 = 72
d
59 − 7 = 52
a
24 − 10 = 14
b
41 − 10 = 31
c
52 − 20 = 32
d
38 − 20 = 18
22 + 6 = 28
b
37 – 5 = 32
11 a
3 + 6 + 7 = 16
b
3 + 7 = 10
10 + 6 = 16
0 + 7 + 10 = 17
0 + 10 = 10
10 + 7 = 17
2
c
1 + 5 + 8 = 14
d
1 + 1 + 8 = 10
10 + 4 = 14
2 + 9 + 5 = 16
1 + 9 = 10
1 + 10 + 5 = 16
3
a
4
27 − 3 = 24
14 + 10 = 24
34 − 10 = 24
29 − 4 = 25
29 – 4 = 25 has a different answer to the others.
Challenge
12 a  58
+ 20
b  62
+ 7
c  46
+ 20
  78
  69
  66
d  83
+ 6
e  55
+ 30
f  71
+ 8
  89
  85
   79
Practice
5
13 4 + 16 = 20 or 14 + 6 = 20. Accept the same but
reordered number sentences.
14 0 + 90 = 90, 10 + 80 = 90, 20 + 70 = 90,
30 + 60 = 90, 40 + 50 = 90.
6
15 Answers depend on how learners choose to
add the numbers unless there is a known
complement to 10. Possible solutions include:
7 + 3 + 8 = 18
7 + 3 = 10
10 + 8 = 18
6 + 8 + 5 + 2 = 21
8 + 2 = 10
10 + 6 + 5 = 21
2 + 3 + 4 + 5 = 14
5 + 2 + 3 = 10
10 + 4 = 14
3 + 4 + 7 + 8 = 22
10 + 4 + 8 = 22
10 + 10 + 2 = 22
5 + 6 + 7 + 8 = 26
11 + 7 + 8 = 26
11 + 10 + 5 = 26
1 + 4 + 5 + 8 + 9 = 27
10 + 4 + 5 + 8 = 27
10 + 10 + 2 + 5 = 27
16 Example:
a
57 − 4 = 53
b
88 − 3 = 85
c
69 − 5 = 64
d  48
− 5
e  89
− 8
f  77
− 7
  43
  81
  70
e  89
f  45
− 30
− 20
  59
  25
a
57 −10 = 47
b
94 − 20 = 74
c
66 − 30 = 36
d  78
− 10
  68
7
a
8
32 + 5 ✓
b
42 − 20 = 22
35 + 30 = 65
  45
− 20
  52
+ 40
  99
− 8
  25
  92
  91
9
52
8
3
4
1
5
9
10 a
6
7
2
11  68
+ 30
  83
− 3
  79
− 7
  66
− 60
  98
  80
  72
   6
If learners struggle, suggest that putting 5 in
the middle square might help. A further hint
could be to think about complements of 10,
because 10 + 5 = 15.
8
a
Challenge
68 − 5 = 63
b
32 + 30 = 62
12 41
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
Exercise 5.3
13 45, 60, 18
Focus
14 Pyramid 1 (5, 1, 2) middle row 5, 2; top
row 10. Pyramid 2 (2, 2, 5) middle row 4, 10;
top row 40. Pyramid 3 (2, 1, 10) middle
row 2, 10; top row 20.
1
10 + 10 + 10 + 10 + 10 = 50 and/or
10 × 5 = 50
2
5 + 5 + 5 + 5 = 20 and/or 5 × 4 = 20
3
2 + 2 + 2 + 2 = 8, 2 × 4 = 8
4
10 × 3 = 30 5
Learner’s own answer.
6
2×1=2
2×4=8
2 × 7 = 14
2 × 10 = 20
Exercise 5.4
Focus
2 × 8 = 16
1
2×2=4
2 × 5 = 10
2 × 8 = 16
2×3=6
2 × 6 = 12
2 × 9 = 18
Practice
7
8
9
5 + 5 + 5 + 5 + 5 = 25, 5 × 5 = 25
b
4 jumps of 2 from 8 to 0 on the
number line, 8 ÷ 2 = 4.
2
a
20 ÷ 10 = 2
3
15 ÷ 5 = 3 and/or 15 ÷ 3 = 5
4
20 ÷ 5 = 4
Multiplication
10 = 10
10 × 1 = 10
10 + 10 + 10 = 30
10 × 3 = 30
5+5+5+5+5+5+
5 + 5 = 40
5 × 8 = 40
5 + 5 + 5 + 5 + 5 + 5 = 30
5 × 6 = 30
6
45 ÷ 5 = 9
2 + 2 + 2 + 2 + 2 + 2 = 12
2 × 6 = 12
7
Learner’s own answers.
2+2=4
2×2=4
Learner’s own arrays, with 2 columns of 9
and 6 columns of 5, or 9 columns of 2 and 5
columns of 6.
Double
Addition
5
b
8
9 jumps of 10 on the number line from
90 to 0, 90 ÷ 10 = 9.
a
12 ÷ 2 = 6
c
70 ÷ 10 = 7
a
multiply 2 × 3 = 6
b
divide 18 ÷ 2 = 9
Challenge
Double 10 is 20 10 + 10 = 20
10 × 2 = 20
Double 1 is 2
1+1=2
1×2=2
9
Double 2 is 4
2+2=4
2×2=4
Challenge
12
×
1
2
5
10
1
1
2
5
10
2
2
4
10
20
5
5
10
25
50
10
10
20
50
100
20 ÷ 2 = 10
a10 jumps of 5 on the number line from
50 to 0, 50 ÷ 5 = 10.
Multiplication
11 6, 5, 40
b
Practice
Repeated addition
10
9
a4 jumps of 5 from 20 to 0 on the
number line, 20 ÷ 5 = 4.
30 ÷ 5 = 6
b
40 ÷ 5 = 8
30 ÷ 6 = 5
10 a
divide 100 ÷ 10 = 10
b
multiply 2 × 9 = 18
11 Learner’s own answer. For example, there
are 60 cherries and 10 children. How many
cherries does each child get?
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
6 Money
7 Time
Exercise 6.1
Exercise 7.1
Focus
Focus
1
100
1
2
Even value: missing US$2 banknote. Not even
value: missing US$5 banknote.
For example, lunch time, TV programme, film,
football match.
2
second, minute, hour, month, year
3
7, 12
4
2nd, 29th, 21st, 5th
5
a
Friday 12th November 2021
b
Sunday 5th December 2021
c
Tuesday 30th November 2021
a
13/07/20
c
23/02/22
3
4
5
Any combination of coins which makes
25c, for example, 1 quarter dollar (25c), or
2 dimes (10c) and 1 nickel (5c), or 5 nickels (5c).
Any combination of banknotes which makes
US$30, for example, US$20 and US$10,
or 3 US$10 or 6 US$5.
Any combination of banknotes and coins
which makes US$5 and 45c, for example,
US$5, 4 dimes and a nickel or 2 US$2, US$1,
a quarter dollar and 2 dimes.
Practice
10
6
7
b
11/09/21
Answers will depend on current date.
Practice
6
35c
7
Banknotes and coins with one or 1 on
(or similar wording).
8
Any combination of banknotes which makes
US$62 and 15c, for example, US$50, US$10,
US$2 and 3 nickels or 3 US$20, US$2, 1 dime
and 1 nickel.
8
For example, sing a song, sneeze, watch a film.
In order of shortest to longest: sneeze, sing a
song, watch a film.
9
a
1st
b
31st
c
21st
d
30th
10 Saturday 14th May 2022
14/05/22
Challenge
Tuesday 17th May 2022
17/05/22
9
Thursday 9th June 2022
09/06/22
Wednesday 22nd June 2022
22/06/22
US$5 and 5c coin, US$1 coin and 1 dime coin.
10 For example, 70c: Marcus half dollar and
2 dimes; Sofia 2 quarter dollars, 1 dime
and 2 nickels. 85c: Marcus half dollar,
quarter dollar, dime; Sofia half dollar,
3 dimes and 1 nickel.
11 a
11
Challenge
Country
or region
Lower value
unit
Higher value
unit
Your
country
Own lower
value unit, if
relevant
Own higher
value unit, if
relevant
USA
c
$
European
Union
c
€
Japan
none
¥
UK
p
£
c
July
b
September
February
d
November
12 year, month, week, weekend, day, hour,
minute, second
13 September and December; May; August.
Sunday 1st January 2023
Friday 31st December 2021
14 Friday 29th May
15 Saturday 14th August
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
8 Numbers to 100 (2)
Exercise 8.2
Exercise 8.1
1
Focus
a
1
b
2
c
3
d
4
e
5
f
7
2
a
16 ÷ 2 = 8
3
a
1
b
2
c
3
d
5
e
5
f
2
a
16 ÷ 4 = 4
Focus
1
2
3
a
fifty-three
b
seventy-one
c
twenty-nine
d
forty-seven
a
86
b
34
c
47
d
62
a
10s
1s
10s
b
1s
4
1
of 16 = 8
2
b
1
of 16 = 4
4
b
Practice
4
5
a
50
b
70
c
50
d
40
e
30
f
90
For example, 20 + 4, 10 + 14, 11 + 13, 12 + 12,
10 + 10 + 4, 10 + 10 + 3 + 1.
Practice
6
fifty-one, fifty-four, fifty-five, sixty-one,
sixty-four, sixty-five, ninety-one, ninety-four,
ninety-five; 9 numbers.
7
54
8
Zara needs to look at the ones to round to the
nearest 10. 5 ones would round up to the next
10, but 50 is 5 tens and 0 ones. It is already a
tens number so does not need to be rounded.
9
For example, 20 + 10 + 5, 21 + 12 + 2,
21 + 13 + 1, 20 + 11 + 4.
Challenge
1
2
6
It is the denominator. It represents how many
equal parts the whole has been split into.
7
Learner should draw 5 marbles.
8
2
9
20
10 1 + 1 + 1 = three-quarters (or 3 ) or
4
4
4
4
1 1 1 1 1
+ = , + = three-quarters.
4 4 2 2 4
11 1 + 1 + 1 + 1 = 4 = 1
4
4
4
4
4
Challenge
12 3, 8
13 2 of 12 and 12 ÷ 2 = 6 ticked.
4
14 Marcus used 1 . Zara used 1 .
10 a
sixty-two
b
seventy-one
c
fifty-nine
d
forty-seven
2
thirty-seven add twenty equals fifty-seven
15 a
b
ninety-nine subtract (or take away) seven
equals ninety-two
b
13 30 metres, 50 metres
14 The other two numbers must total 26, for
example, 20 + 6, 16 + 10, 13 + 13, 12 + 14,
11 + 15.
4
Arun and Zara used 1 + 1 = 1 .
4 4 2
11 a
12 60 centimetres, 90 centimetres
11
5
1
2
8 pieces. Yes, all pieces are 1 , so any
4
8 pieces will make 2 whole sandwiches.
16 Swap the dollar for 4 quarters (quarter dollar)
coins and give 1 to your friend.
25 c
25 c
25 c
25 c
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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
9 Statistics (2)
Exercise 9.2
Exercise 9.1
1
Chocolate was the most popular. Coffee was
the least popular. 16 ice creams were eaten.
2
Team B has scored most goals. Team E has
scored the least goals. 1 more goal was scored
by Team B than Team D. Team E scored
2 goals fewer than Team A.
Focus
Focus
Numbers
Odd
9
2
3
More than 20
25
13
21
62
78
Flies, walks. But learners may decide on
different labels.
Practice
3
5 like orange juice. 2 like water. Cola was
liked by 3 children. 2 more children preferred
milk to tea. 16 children were asked altogether.
Learner’s own answer.
4
Ara’s family name has 6 letters. Ohan’s family
name has 7 letters. Akila’s family name has
8 letters.
Learner’s own answers.
Practice
4
Akila’s family name has most letters. Kai’s
family name has least letters.
Red: apple, strawberry, cherries, pepper,
tomatoes.
Ohan’s family name has 3 more letters than
Kai’s family name.
Green: apple, lime, avocado, kiwi fruit,
broccoli.
Ara’s family name has 2 fewer letters than
Akila’s family name.
Red and green in the overlap: apple, mango.
5
6 12 5 23
6
Learner’s own answer.
Learner’s own questions.
Challenge
Challenge
7
29 pieces of fruit in the bowl. 1 more pear.
1 fewer banana. Most fruit is apples. Least
fruit is mango.
6
Use of digits in 5 telephone numbers
Cats in the cat shelter
Grey
Large
Poppy
Tilly
12
5
Magic
Scrumpy
8
Learner’s own answer.
9
41, 84, 59, 16, 25, 75
Jack
Monty
Number of times used
1
0
Milk
41
Sugar
84
Sugar but not milk
59
Milk but not sugar
16
Milk and sugar
25
Milk or sugar
75
1
2
3
4
5
6
7
8
9
Learner’s own questions.
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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
10 Calculating
6
Exercise 10.1
Focus
1
53
31
63
71
23
61
32
63 + 25 = 53 + 35 and 37 − 12 = 39 − 14 ticked,
possible corrections include
53 + 24 = 54 + 23 and 85 − 33 = 95 − 43.
= 30 + 2 + 20 + 6
8
51 and 97.
= 30 + 20 + 2 + 6
Challenge
= 50 + 8
9
32 + 26
= 58
b
21
7
Accept reordering of the numbers.
a
42
10
41 + 35
Smallest total 13 + 24 = 37 or 14 + 23 = 37.
Greatest total 52 + 43 = 95 or 53 + 42 = 95.
1
= 40 + 1 + 30 + 5
7
2
5
= 40 + 30 + 1 + 5
= 70 + 6
7
= 76
c
3
5
3
6
8
6
5
4
9
4
7
1
9
8
23 + 34
10
= 20 + 3 + 30 + 4
6
11
12
3
7
13
4
= 20 + 30 + 3 + 4
14
= 50 + 7
2
4
1
= 57
2
d  57
+ 21
e  43
+ 14
f  23
+ 24
Exercise 10.2
  78
  57
   47
Focus
1
Calculation
Inverse
7 + 3 = 10
10 − 3 = 7
13 + 5 = 18
18 − 5 = 13
32 + 17 = 49
49 − 17 = 32
8−6=2
2+6=8
46 − 12
19 − 12 = 7
7 + 12 = 19
= 40 − 10 + 6 − 2
28 − 15 = 13
13 + 15 = 28
38 − 25
= 30 − 20 + 8 − 5
= 10 + 3
= 13
= 30 + 4
= 34
3
a
4
34 − 21 = 13, 67 − 46 = 21
27 + 12 = 39
Practice
5
13
b
33 + 24 = 57
2
For example, 13 + 7 = 20, 20 − 7 = 13.
3
5 + 1 = 6
6=5+1
1 + 5 = 6
6=1+5
6 − 1 = 5
5=6−1
6 − 5 = 1
1=6−5
Learner’s own answers.
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Practice
4
5
6
7
8
a  27
− 12
b  11
+ 23
  15
  34
c  87
− 35
d  32
+ 64
  52
  96
a  33
+ 24
b  49
− 27
  57
  22
c  76
− 42
d  65
+ 14
  34
  79
13 + 7 = 20
13 + 15 = 28
20 = 13 + 7
28 = 13 + 15
7 + 13 = 20
15 + 13 =28
20 = 7 + 13
28 = 15 + 13
20 − 13 = 7
28 − 13 = 15
7 = 20 − 13
15 = 28 − 13
20 − 7 = 13
28 − 15 = 13
13 = 20 − 7
13 = 28 − 15
90 − 50 = 40
40 = 90 − 50
90 − 40 = 50
50 = 90 − 40
a54 + 35: estimate 50 + 40 = 90;
54 + 35 = 89; inverse 89 − 35 = 54.
b
77 − 44: estimate 80 − 40 = 40;
77 − 44 = 33; inverse 33 + 44 = 77.
11 40 + 34 = 74, 74 − 34 = 40
41 + 33 = 74, 74 − 33 = 41
42 + 32 = 74, 74 − 32 = 42
43 + 31 = 74, 74 − 31 = 43
44 + 30 = 74, 74 − 30 = 44
Other solutions require regrouping of ones,
which is beyond Stage 2 expectations.
12 69 − 42 = 27, 27 + 42 = 69
68 − 41 = 27, 27 + 41 = 68
67 − 40 = 27, 27 + 40 = 67
Other solutions require regrouping of ones,
which is beyond Stage 2 expectations.
Exercise 10.3
Focus
1
10 × 4 = 40, 5 × 3 = 15, 10 × 9 = 90
2
Multiplying by 2
Doubling
1×2=2
1+1=2
10 × 2 = 20
10 + 10 = 20
2×2=4
2+2=4
5 × 2 = 10
5 + 5 = 10
3
10 × 1 = 10 → 1 × 10 = 10, 2 × 5 = 10
or 5 × 2 = 10;
2 × 10 = 20 → 10 × 2 = 20, 4 × 5 = 20 or 5 × 4 = 20;
4 × 2 = 8 → 2 × 4 = 8, 1 × 8 = 8 or 8 × 1 = 8.
4
4×1=2×2
Practice
5
Challenge
9
a  53
+ 45
b  47
− 33
  98
  14
c  86
− 61
d  42
+ 53
  25
  95
10 The two numbers that are added together to
find the complement are the same (30). There
are only 2 possible subtractions. The related
subtractions are 60 − 30 = 30 and 30 = 60 − 30.
14
1 × 5 = 5 and 9 × 5 = 45
2 × 5 = 10 and 8 × 5 = 40
3 × 5 = 15 and 7 × 5 = 35
4 × 5 = 20 and 6 × 5 = 30
1 × 10 = 10 and 4 × 10 = 40
2 × 10 = 20 and 3 × 10 = 30
6
7
3 × 2
10 + 10
10 × 2
6+6
1 × 2
3+3
6 × 2
1+1
1 × 5 = 5, 2 × 5 = 10
5 × 5 = 25 or 10 × 5 = 50
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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
Challenge
6
Division fact
Fraction fact
18 ÷ 2 = 9
1
of 18 = 9
2
8
10, 20, 30, 40, 50. Numbers with 5 ones
are not multiples of 10. 5 × 2 = 10, so only
multiples of 10 are in both tables.
9
Biscuits cost a nickel each, 5c. The calculation
should be 5 × 4 = 20, 20c.
14 ÷ 2 = 7
1
of 14 = 7
2
Cakes cost a dime each, 10c. The calculation
10 × 7 = 70, 70c is correct.
16 ÷ 4 = 4
1
of 16 = 4
4
4÷4=1
1
of 4 = 1
4
10 1 × 7, 2 × 6, 5 × 3, 5 × 4, 10 × 3, 10 × 5.
Exercise 10.4
Challenge
Focus
1
2
10 × 1 = 10
10 ÷ 10 = 1
10 × 2 = 20
20 ÷ 10 = 2
10 × 3 = 30
30 ÷ 10 = 3
10 × 4 = 40
40 ÷ 10 = 4
10 × 5 = 50
50 ÷ 10 = 5
10 × 6 = 60
60 ÷ 10 = 6
10 × 7 = 70
70 ÷ 10 = 7
10 × 8 = 80
80 ÷ 10 = 8
10 × 9 = 90
90 ÷ 10 = 9
10 × 10 = 100
100 ÷ 10 = 10
7
Zara’s: 8 cubes, 1 of 16 = 8, 16 ÷ 2 = 8.
2
Arun’s: 4 cubes, 1 of 16 = 4, 16 ÷ 4 = 4.
4
8
40 ÷ 10, 1 of 20, 1 of 12, 18 ÷ 2, 6 × 2.
9
More than 4 of the following:
4
2
1 × 8 = 2 × 4 = 8 ÷ 1 = 16 ÷ 2 = 40 ÷ 5 = 80 ÷ 10 =
1
of 16.
2
11 Geometry (2)
Exercise 11.1
2×3=6 → 6÷2=3
Focus
1×5=5 → 5÷1=5
1
5 × 7 = 35 → 35 ÷ 5 = 7
3
×
5 × 2 = 10 ÷ 1 or 20 ÷ 2 or 50 ÷ 5 or 100 ÷ 10
×
9 × 1 = 9 ÷ 1 or 18 ÷ 2 or 45 ÷ 5 or 90 ÷ 10
Practice
4
5 × 4 = 20, 20 ÷ 5 = 4; 3 × 10 = 30, 30 ÷ 10 = 3.
5
Any paired multiplication and division facts
that are equivalent in value.
Start
×
×
5 turns; 2 anticlockwise turns;
3 clockwise turns.
2
15
×
Learner’s own answer.
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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
3
Shape
Predict
Check
Learner’s
own
prediction
once
Learner’s
own
prediction
once
Learner’s
own
prediction
4 times
Learner’s
own
prediction
6
Three half turns will give the same answer as
one half turn.
Challenge
twice
7
Learner’s own answer.
8
a
I can make two quarter turns clockwise.
An equilateral triangle
b
Practice
4
Learner’s own answer.
5
a
I can make a half turn anticlockwise.
Learner’s answers can include:
•
one quarter turn anticlockwise
•
one half turn clockwise then one
quarter turn clockwise
•
three quarter turns clockwise
•
one quarter turn clockwise then one
half turn clockwise.
9
b
c
Exercise 11.2
Focus
1
The final circle shows the centre dot.
Learner’s own answer.
Practice
2
16
4 centimetres, 5 centimetres, 6 centimetres
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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
Challenge
Practice
3
5
Learner draws a further 5 lines, which would
mean there would be 12 lines coming from the
centre to the edge. All lines coming from the
centre should be the same length.
12 Telling the time
11 12 1
10
2
9
3
8
4
7
6
5
9
3
Focus
8
4
1
4:10 10:25 8:15 6:05
2
Analogue clocks showing quarter past 6,
twenty minutes past 7, five minutes past 5,
twenty-five minutes past four.
11 12 1
10
2
3
4
7
6
5
6
11 12 1
10
2
9
8
7
6
5
7
4
6
5
9
3
8
4
7
3:45
4
6
5
7
6
5
11:55
9
3
8
4
7
6
5
14:35
11 12 1
10
2
10:10
9
3
8
4
7
6
5
3
Challenge
4
7
Learner’s own answer. Words and clocks
matching in each column.
8
Row 1:
9
3
8
4
9
5
8
11 12 1
10
2
11 12 1
10
2
6
3
6:20
Clocks showing the correct times.
Quarter past 9: 09:15, Morning.
Quarter to 7: 06:45, Evening.
Quarter to 4: 03:45, Afternoon.
11 12 1
10
2
7
9
11 12 1
10
2
3
8
8:25
11 12 1
10
2
Exercise 12.1
9
11 12 1
10
2
8
3
7
6
5
4
15 minutes
Row 2:
Row 3: ring around 10 minutes past 8.
Row 4: ring around 20 minutes past 10.
17
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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
9
Quarter of an hour is 15 minutes, not
25. Half an hour is 30 minutes not 50.
Some people may think that, for example,
quarter past 9 is 9:25 and half past 9 is 9:50.
13 Measures (2)
Exercise 13.1
Focus
1
Pear mass is 20 grams.
b
Scales should show 70 grams.
c
Scales should show 50 grams.
50 grams flour, 1 egg, 25 grams sugar.
3
Caterpillar 3 grams. Bug 1 gram. 3 pencils
15 grams.
4
Scales should show: 5 kilograms, 8 kilograms,
7 kilograms.
5
a2 frogs = 6 blocks. 1 frog = 3 blocks.
Taking away 1 frog will make the scales
dip on the blocks side.
1 frog is lighter than 6 blocks.
2 frogs = 8 sweets. 1 frog = 4 sweets. When
taking away 3 sweets, the frogs would be
lower than the sweets.
2 frogs are heavier than 5 sweets.
6
8
18
Brick
✓
Baby
✓
Cat
✓
Mouse
✓
Fly
✓
No, larger objects are not always heavier than
smaller objects.
Learner’s own answer.
11 If the temperature increases, the number
increases/gets larger.
If the temperature decreases, the number
decreases/gets smaller.
a
10 °C
b
15 °C
d
18 °C
e
19 °C
c
12 °C
Challenge
12 Learner’s own answer.
13 a
7 kilograms
b
6 kilograms
c
5 kilograms
d
2 kilograms
Another pebble would make the pebble
side lower than the side with the bird.
14 There are many answers. For example,
100g can be 50 + 50, 10 × 10, 5 lots of 20,
100 × 1, 20 lots of 5 or 50 lots of 2.
2 pebbles are heavier than 1 bird.
15 a
Learners can give any pairs of temperatures
that have a difference of 9.
Practice
7
Less than About
More than
1 kilogram 1 kilogram 1 kilogram
10 Learner’s own answer.
2
c
Object
Learner’s own answer for final two rows.
a
b
9
9 grams
54 grams
26 grams
82 grams
32 grams
100 grams
56 grams
90 grams
14 kilograms
5 grams
1 grams
26 grams
12 kilograms
10 kilograms
b
40 cubes will balance 1 pineapple.
9 cubes will balance 1 pear.
16 Both thermometers show the same
temperatures of 40 °C.
One thermometer shows the scale going up in
5s, the other shows it going up in 10s.
One thermometer shows temperatures up to
50 °C and the other will record temperatures
up to 100 °C.
The learners should have drawn a line on each
thermometer up to the given value.
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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
Exercise 13.2
Focus
1
6 millilitres
72 millilitres
100
100
a
Jugs: more, less.
90
90
b
Bowls: less, more.
80
80
c
Drinks: less, more.
70
70
d
Dishes: less, more.
60
60
2
Milk more, spoon less, bucket more, cup less,
carton less.
50
50
40
40
3
1
litre. 1 litre. 5 litres.
2
30
30
4
Bucket 9 litres, squash 1 litre, fish tank
50 litres.
20
20
10
10
Practice
5
2 litres
6
Jug 1: 7 millilitres; jug 2: 80 millilitres;
jug 3: 35 millilitres; jug 4: 55 millilitres
Challenge
7
Yes, the teacher has enough water.
There is 1 litre left in the teacher’s bottle.
8
3 litres
9
a
14 Pattern and
probability
Exercise 14.1
Focus
1
litre
2
1
4 b 4 c 2
1st pattern is alternate white and black.
2nd pattern is black, grey, white repeated.
10 15 millilitres
60 millilitres
2
Learner’s own answer.
100
100
3
Marble and pencil.
90
90
80
80
70
70
60
60
50
50
40
40
30
30
20
20
10
10
Practice
4
Learner’s own answer.
5
Learner’s own answer.
6
Learner’s own answer.
Challenge
7
Learner’s own answer.
You would see a regular pattern on fabric,
wallpaper, floor tiles or in the bricks on
a house.
You see a random sequence where there
is no regular pattern, for example in some
mosaic designs.
8
19
Learner’s own answer.
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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
9
Learners do not need to name the shapes,
merely draw them.
The sequence is a pattern of three shapes.
The first shape is always a square; the
last shape is always a hexagon; the centre
shape changes.
5
15 Symmetry, position
and movement
6
Exercise 15.1
a
b
11 12 1
10
2
11 12 1
10
2
9
3
9
3
8
4
8
4
7
5
7
6
5
6
12
11 12 1
10
2
11 12 1
10
2
9
3
9
3
8
4
8
4
Focus
1
6
7
6
5
7
6
5
12
9
11 12 1
10
2
11 12 1
10
2
9
3
9
3
8
4
8
4
7
6
5
3
7
6
5
6
Challenge
7
2
a
3
a
b
6
b
6
c
3
d
9
Practice
4
For example:
20
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CAMBRIDGE PRIMARY MATHEMATICS 2: TEACHER’S RESOURCE
9
Learner’s own answer.
8
10 aQuarter turn clockwise; three-quarters
turn anticlockwise.
21
b
Quarter turn anticlockwise; three-quarters
turn clockwise.
c
Half a turn clockwise; half a turn
anticlockwise.
d
Full turn clockwise; full turn
anticlockwise.
Cambridge Primary Mathematics 2 – Moseley & Rees © Cambridge University Press 2021
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