MATHS TEXT BOOK Y5 DLP

Days and hours

1 The sailing time for an expedition from Sailing Expedition
location A to location E is shown in the
diagram. A 5
8
1 days

a Calculate the total sailing time from B
location A to location C.

1 85 days + 1 41 days = days 1
4
1 58 1 41 1 85 1 41 × 2 1 days
× 2
days + days = days + days C

= 1 85 days + 1 82 days 1 day 5 hours

= 2 87 days DE

1 85 days + 1 41 days = 2 87 days 1 1 days
6

The total sailing time from location A to location C is 2 87 days.

b What is the total sailing time, in days and hours, from
location C to location E?

1 day 5 hours + 1 61 days = days hours

1 61 days = 1 day + 1 day
6
day hour
= 1 day + (61 × 4 hours
1 5
24) +1 4
9
1 2
= 1 day + 4 hours

= 1 day 4 hours

1 day 5 hours + 1 61 days = 2 days 9 hours

The total sailing time from location C to location E
is 2 days 9 hours.

4.3.1 (ii) • Adding fractions of days is similar to adding fractions by getting 143
the common denominators first before doing addition.

2 R efer to the following table and Process Duration
calculate the total duration 3.5 days
of the two processes for completing Preparation,
a robotic car. installation, and 1.5 days
3.5 days + 1.5 days = days finishing of
non-metallic
1 materials and
metallic materials
3.5 days
+ 1 .5 days Installation of the
alarm system
5.0 days

3.5 days + 1.5 days = 5 days

The total duration of the two processes is 5 days.

3 4 .75 days + 9 days 18 hours = days hours hour
day
4.75 days = 4 days + 0.75 day 1
= 4 days + (0.75 × 24) hours 4
= 4 days + 18 hours + 9 18
= 4 days 18 hours 18
13 36
+1 − 24
12
14

4.75 days + 9 days 18 hours = 14 days 12 hours

4 3  21 days + 8.125 days = days hours

3 1 days = 3 days + 1 day 8.125 days = 8 days + 0.125 day
2 2 = 8 days + (0.125 × 24) hours
= 8 days + 3 hours
= 3 days + (21 × 12 hours = 8 days 3 hours

24)

1

= 3 days + 12 hours

= 3 days 12 hours

day hour

3 12
+8 3

3 21 days + 8.125 days = 11 days 15 hours 11 15

144 4.3.1 (ii) • Carry out mental arithmetic activities, such as 1 day is 12 hours,
4.3.2 (ii) 2

0.5 day is 12 hours, and 0.25 day is 6 hours.

Years and months
1 The duration to complete three phases of

Indah Housing Project is shown below.

Phase 1 2 21 years Phase 2 3 41 years Phase 3 5 years 9 months

a Calculate the total duration for Phase 1 and Phase 2.

2 21 years + 3 41 years = years

2 21 years + 3 41 years = 2 21 × 2 years + 3 41 years
× 2

= 2 2 years + 3 1 years

44

= 5 34 years

2 21 years + 3 41 years = 5 34 years
The total duration for Phase 1 and Phase 2 is 5 34 years.

b Determine the total duration, in years and months, Is the
for Phase 1 and Phase 3. calculation

2 21 years + 5 years 9 months = years months correct?
Discuss.
year month 7 years 14 months
25 = 7 years + 12 months + 2 months
= 7 years + 1 year + 2 months
+5 9

7 14 = 8 years 2 months

4.3.1 (iii) • Stress that 1 is equal to 0.5 and relate that 1 year is equal to 145
2 2

6 months.

2 a Based on the brochure, total up the COMPUTER COURSE
duration of the basic and advanced
levels for a computer course. Basic level 1.25 years

1.25 years + 1.5 years = years Advanced level 1.5 years

1 .25 years Professional level 5 year
+ 1 .50 years 6

2.75 years DISFSPOCEROCIUTAHNLETS
REGFIISRTSRTA5T0IONS
1.25 years + 1.5 years = 2.75 years

The total duration of the basic and
advanced levels for a computer course
is 2.75 years.

b W hat is the duration of the basic and professional levels for the
computer course? State your answer in years and months.

1.25 years + 5 year = years month
6

1.25 years = 1 year + 0.25 year year month
= 1 year + (0.25 × 12) months 13
= 1 year 3 months
+ 10
5 year = (65 × 2 months
6 1 13
12)
+ 1 − 12
1
21
= 10 months

1.25 years + 5 year = 2 years 1 month
6

The duration of the basic and professional levels for the
computer course is 2 years 1 month.

3 year + year = 1 year
4

State the value in decimals.

146 4.3.1 (iii)
4.3.2 (iii) • Carry out a quiz where pupils are able to answer spontaneously.

Decades and years

1 The following diagram shows the reign of the Malacca Sultanate.

Sultan Muzaffar Sultan Sultan Alauddin Sultan

Shah Mansur Shah Riayat Shah Mahmud Shah

1 51 decades 1 190 decades 1110 decades 23 years

Source: https://rb.gy/02uepq

a Calculate the total reign of Sultan Muzaffar Shah and
Sultan Mansur Shah.

1 51 decades + 1 190 decades = decades

1 51 decades + 1 190 decades = 1 51 × 2 decades + 1 190 decades
× 2

= 1 120 decades + 1 190 decades

= 2 1101 decades 11
10
= 2 decades + decades

= 2 decades + 1 110 decades
= 3 110 decades

1 51 decades + 1 190 decades = 3 110 decades

The total reign of Sultan Muzaffar Shah and Sultan Mansur Shah
is 3 110 decades.

b C alculate the reign of the last two sultans.

1 110 decades + 23 years = years

1 110 decades = ( 11 × 10) years 1 1 years
10 + 2 3 years

= 11 years 3 4 years

1 110 decades + 23 years = 34 years

The reign of the last two sultans is 34 years.

4.3.1 (iv) • Discuss the history of the Malacca Sultanate in ancient times. 147
Instil the moral value of love for the country.

2 B ased on the table, calculate Service duration
Encik Mirza’s duration of service, School Duration
in decades, before he retired. SK Sri Intan 2.4 decades

2.4 decades + 0.8 decade = decades SK Melati 0.8 decade

1

2.4 decades
+ 0.8 decade

3.2 decades

2.4 decades + 0.8 decade = 3.2 decades

Encik Mirza’s duration of service before he
retired is 3.2 decades.

3 I was a temporary school How many years has Miss Alice served
1 as a teacher?
teacher for 5 decade. For the
1
next 1.3 decades, 5 decade + 1.3 decades = years

I am a permanent teacher.

MeCthaorad 1

1 decade = 0.2 decade
5

CMaertaho2d 2 0.2 decade 1.5 decades
+ 1 .3 decades = (1.5 × 10) years
= 15 years
1 .5 decades

1 decade = (51 × 2 years 1.3 decades = (1.3 × 10) years
5 = 13 years
10)

1

= 2 years

2 years + 13 years = 15 years

1 decade + 1.3 decades = 15 years
5

Miss Alice has served as a teacher for 15 years.

Give the answer of 3.9 decades add 51 years, in decades.

148 4.3.1 (iv)
4.3.2 (iv) • Discuss a few calculation strategies to obtain the answer.

Centuries and decades 6 51 centuries + 3 21 centuries = centuries
1 Cave A is 6 51 centuries old.
6 51 centuries + 3 21 centuries
Cave B is 3 21 centuries older
than Cave A. = 6 51 × 2 centuries + 3 21 × 5 centuries
× 2 × 5
The age of
Cave B is ... = 6 120 centuries + 3 150 centuries

= 9 170 centuries

6 51 centuries + 3 21 centuries = 9 170 centuries

2 130 century + 29 decades = decades

3 century = (130 × 10) decades 1
10
3 decades
= 3 decades + 29 decades

32 decades

3 century + 29 decades = 32 decades
10

3 2  45 centuries + 8 centuries 7 decades = centuries decades

2 45 centuries = 2 centuries + 4 century century decade
5
2 8
= 2 centuries + (54 × 2 decades + 8 7

10) 1 0 1 5
+ 1 − 1 0
1
1 1 5
= 2 centuries 8 decades

2 54 centuries + 8 centuries 7 decades = 11 centuries 5 decades

State 11 centuries 5 decades in decades. 149
4.3.1 (v)

4 E stimate the age, in centuries, The number of rings on the
of tree B. cross-section of tree A indicates
that tree A is about 0.2 century old.

0.2 century + 0.3 century = century Cross-section
of tree A
0.2 century
+ 0.3 century Cross-section
of tree B
0.5 century
0.2 century + 0.3 century = 0.5 century

The estimated age of tree B is about Tree B is 0.3 century older
0.5 century. than tree A.

5 12.6 centuries + 58 decades = centuries decades

12.6 centuries = 12 centuries + 0.6 century century decade
= 12 centuries + (0.6 × 10) decades 12 1 6
= 12 centuries 6 decades
+ 58
12 64

+ 6 − 6 0
18 4

12.6 centuries + 58 decades = 18 centuries 4 decades

6 Add 4 190 centuries and 3.2 centuries. Give the answer in centuries
and decades.

4 190 centuries + 3.2 centuries = centuries decade

9 century = ( 9 × 10) decades 4 190 centuries = 4 centuries 9 decades.
10 10 3.2 centuries = 3 centuries 2 decades.

= 9 decades century decade

0.2 century = (0.2 × 10) decades 4 9
= 2 decades +3 2

7 1 1

+ 1 − 1 0

8 1

4 190 centuries + 3.2 centuries = 8 centuries 1 decade

150 4.3.1 (v) • Provide more exercises on constructing number sentences orally
4.3.2 (v) using flash cards.
• Surf https://rb.gy/rfusfb

Centuries and years Estimate the age of the Alor Setar
1 Estimated age in 2021 Clock Tower.

The Kuala Kangsar 4 century + 3 century = centuries
Clock Tower 5 10

about 4 century old 4 century + 3 century
5 5 10

Source: http://rb.gy/uhx8hq = 4 × 2 century + 3 century
5 × 2 10

The Alor Setar = 8 century + 3 century
Clock Tower 10 10

3 = 11 centuries
10 10
about century older
= 1 110 centuries
than the Kuala Kangsar

Clock Tower 4 century + 3 century = 1 110 centuries
5 10

The estimated age of the Alor Setar Clock Tower is about 1 110 centuries.

2 2  170 centuries + 60 years = years

2  170 centuries = (2 × 100) years + (170 × 100) years 1

= 200 years + 70 years 270 years
+ 60 years
= 270 years
330 years

2 170 centuries + 60 years = 330 years

3 8 21 centuries + 1 century 35 years = centuries years

8 21 centuries = 8 centuries + 1 century century year
2 8 50

= 8 centuries + (21 × 50 years + 1 35
9 85
100)

1

= 8 centuries 50 years

8 21 centuries + 1 century 35 years = 9 centuries 85 years

4.3.1 (vi) • Carry out mental arithmetic activities to convert centuries to years 151
and years to centuries.

4 7.9 centuries + 6 centuries 42 years = centuries years

7.9 centuries = 7 centuries + 0.9 century century year

= 7 centuries + (0.9 × 100) years 7 90
= 7 centuries 90 years +6 42
132
13

+ 1 −100

14 32

7.9 centuries + 6 centuries 42 years = 14 centuries 32 years

5 0.82 century + 451 years = centuries years

Convert units of time to years,
as well as centuries and years.

0.82 century = (0.82 × 100) years century year

= 82 years 82
+ 4 51
451 years = 400 years + 51 years
= 4 centuries 51 years 4 133
+ 1 −100

5 33

0.82 century + 451 years = 5 centuries 33 years

6 5 43 centuries + 1.3 centuries = years

First, convert units of time in
fraction to units of time in decimal.

5 34 centuries = 23 centuries 1
4
5.75 centuries
= 5.75 centuries + 1 .30 centuries

7.05 centuries

7.05 centuries = (7.05 × 100) years
= 705 years
5 43 centuries + 1.3 centuries = 705 years

State 705 years in centuries and years.

152 4.3.1 (vi)
4.3.2 (vi) • Encourage pupils to calculate using various methods of calculation.

1 Add.

a 1 hour + 1 hour = hour b 0.25 hour + 3 hours = hours
2 10 days

c 1 61 days + 1 day = days d 6.5 days + 4.75 days =
8

e 9.25 years + 10.5 years = years

f 7 decade + 2 decade = decades
10 5

g 8 53 centuries + 1 21 centuries = centuries

h 8.47 centuries + 52.9 centuries = centuries

2 Calculate.

a 3 hour + 40 minutes = minutes
5
5
b 4 days 20 hours + 8 day = days hours

c 7.5 days + 19 hours = hours

d 1 61 years + 4 years 10 months = years

e 17 years + 1 decade = decade years
5

f 4 decades 1 year + 2.3 decades = years

g 2 25 centuries + 1 century 6 decades = decades

h 66 years +1 190 centuries = centuries years

3 Calculate.

a 5 hour + 0.45 hour = minutes
6
b 7.625 days + 1 21 days =
days hours
months
c 1 43 years + 0.75 year = years

4 Calculate athnedsduemcaodfe2s. 45 centuries and 3.8 centuries. State the answer in
centuries

5 Is the statement on the
right correct? Prove it. 2 .79 centuries + 8 41 centuries = 11 centuries 4 years

4.3.1 153
4.3.2

SUBTRACTION OF TIME Health Poster Project

Hours and minutes Name Time Taken to Complete
1
Raden 3 hour
4

Siti 1 56 hours

Divani 12 minutes earlier than Siti

Raden Divani Siti HEALTHY ME

a B ased on the table above, calculate the AL

difference in time taken to complete the

project by Raden and Siti.

1 56 hours − 3 hour = hours
4
3 1 56 ×2 3 × 3
1 56 hours − 4 hour = ×2 hours − 4 × 3 hour

= 1 1102 hours − 9 hour
12

= 1 112 hours

1 56 hours − 3 hour = 1 112 hours
4
The difference in time taken by Raden and Siti is 1 112 hours.

b H ow long did Divani take, in hours and minutes, to complete her project?

1 65 hours – 12 minutes = hour minutes

1 56 hours = 1 hour + 5 hour hour minute
6
1 4 10
= 1 hour + (56 × 10 minutes –
50
60) 1 12
38
1

= 1 hour 50 minutes

1 65 hours – 12 minutes = 1 hour 38 minutes
The time taken by Divani to complete her project is 1 hour 38 minutes.

154 • Emphasise that before subtracting fractions, get the common

4.3.1 (i) denominators first.
• Guide pupils to understand keywords to determine the operations such

as earlier which means subtraction.

2 Calculate the difference in cooking time, in hours,

between steamed and boiled keropok lekor as

labelled in the pictures. steamed

1.5 hours – 0.5 hour = hour 1.5 hours

1 .5 hours boiled
− 0.5 hour 0.5 hour

1 .0 hour

1.5 hours – 0.5 hour = 1.0 hour

The difference in cooking time between the steamed and the boiled
keropok lekor is 1 hour.

3 3 .45 hours − 1 hour 40 minutes = hour minutes

3.45 hours = 3 hours + 0.45 hour hour minute

2 87 60 minutes
= 3 hours + (0.45 × 60) minutes 3 2 7 + 27 minutes
− 1 40
= 3 hours 27 minutes 1 47 87 minutes

3 .45 hours – 1 hour 40 minutes = 1 hour 47 minutes

4 1 61 hours − 0.35 hour = minutes

1 61 hours = (67 × 10 minutes 0.35 hour 6 10
= (0.35 × 60) minutes
60) 70 minutes
= 21 minutes − 2 1 minutes
1
49 minutes
= 70 minutes

1 61 hours − 0.35 hour = 49 minutes

Complete this.

5 hour – minutes = 3 hour – 1 hour
6 4 6

4.3.1 (i) • Encourage pupils to buy Malaysian products. 155
4.3.2 (i) • Surf https://rb.gy/wjpftb

Days and hours

1 Pattern B
2 41 days
Pattern A
1 31 days

Based on the information above, how much more time is needed to

paint batik pattern B compared to pattern A?

2 41 days − 1 31 days = days

2 41 days − 1 31 days = 2 41 × 3 days − 1 31 × 4 days
× 3 × 4

= 2 132 days − 1 142 days

= 27 days − 16 days
12 12

= 11 day
12

2 41 days − 1 31 days = 11 day
12
11
The time needed to paint batik pattern B is 12 day more than pattern A.

2 9 days 18 hours – 7 day = days hours
8

7 day = (87 × 3 hours day hour • Convert 9 days to
8 8 days 24 hours.
24) 8 42
• Add 24 hours and
1 9 18 18 hours to make 42 hours.
− 21
= 21 hours
8 21

9 days 18 hours – 7 day = 8 days 21 hours
8

Find the difference of time between 10 65 days and
4 21 days. State the answer in hours.

156 4.3.2 (ii) • Drill pupils on subtraction of time using number cards.
• Surf https://rb.gy/1wlvbb

3 Camp Duration
Scouts 2.25 days
Prefect Leadership 1.5 days

Based on the table above, how much
longer is the duration of the scouts camp
than the prefect leadership camp?

2.25 days − 1.5 days = day

1 12

2 . 2 5 days
− 1 . 5 0 days

0 . 7 5 day

2.25 days − 1.5 days = 0.75 day

The duration of the scouts camp
is 0.75 day more than the prefect
leadership camp.

4 Subtract 3 days 5 hours from 9.75 days. Give the answer in
days and hours.

9.75 days − 3 days 5 hours = days hours

9.75 days = 9 days + 0.75 day day hour
= 9 days + (0.75 × 24) hours
= 9 days 18 hours 9 18
−3 5

6 13

9.75 days − 3 days 5 hours = 6 days 13 hours

5 6 .5 days − 7 day = days hours day hour
12

6.5 days = 6 days + 0.5 day 7 day = (172 × 2 hours 5 36
= 6 days + (0.5 × 24) hours 12
24) 6 12
− 14
1

= 6 days 12 hours = 14 hours 5 22

6.5 days − 7 day = 5 days 22 hours
12

4.3.1 (ii) 157
4.3.2 (ii) • Guide pupils to convert days to hours using various methods.

Years and months

1 a Find the age difference, in years, between the

hamster and the rabbit.

10 51 years − 2 21 years = years

10 51 years − 2 21 years hamster’s age: 2 21 years
10 51 × 2 2 21 × 5 rabbit’s age: 10 51 years
= × 2 years − × 5 years

= 10 120 years − 2 150 years

= 9 1102 years − 2 150 years

= 7 170 years
10 51 years − 2 21 years = 7 170 years

The age difference between the hamster and the rabbit
is 7 170 years.

b W hat is the age difference between the hamster and the goldfish?

My goldfish is about 8 years 8 months − 2 21 years
8 years 8 months old. = years months

1 year = ( 21 × 6 months year month
2
12) 8 8
−2 6
1 2
6
= 6 months

Therefore, 2 21 years = 2 years 6 months.

8 years 8 months − 2 21 years = 6 years 2 months
The age difference between the hamster and the goldfish is 6 years 2 months.

State the above answer in months.

158 4.3.1 (iii) • Encourage pupils to use subtraction in vertical form involving
unit conversion.

2 Subtract 16.875 years and 5.625 years.

16.875 years − 5.625 years = years
1 6.875 years

− 5.625 years
1 1 .250 years

16.875 years − 5.625 years = 11.25 years

3 How many more months is 30.25 years from 29 months?

30.25 years − 29 months = months 5 13

30.25 years = (30.25 × 12) months 36 3 months
= 363 months − 2 9 months

33 4 months

30.25 years − 29 months = 334 months

4 14.5 years − 7 43 years = years months

Method 1 14.5 years = 14 years + 0.5 year

= 14 years + (0.5 × 12) months year month

= 14 years 6 months 13 18

7 34 years = 7 years + 3 year 14 6
4 − 7 9
9
(43 3 6

= 7 years + × 12) months

1

= 7 years 9 months

Method 2 3 year = 0.75 year 14.5 years − 7 34 years
4 = 14.5 years − 7.75 years

= 6.75 years

6.75 years = 6 years + 0.75 year
= 6 years + (0.75 × 12) months
= 6 years 9 months

14.5 years − 7 43 years = 6 years 9 months

4.3.1 (iii) • Explain to pupils the way to convert the unit of time from years 159
4.3.2 (iii) to months.

Decades and years I am on my way home to Taman Encik Shamel
Universiti. I have been staying
1 there for nearly 1 45 decades.
Encik Siva

I have been
staying there for
about 3 21 decades.
Let me help you.

How much longer has Encik Shamel been staying in Taman Universiti

compared to Encik Siva?

3 21 decades − 1 45 decades = decades

3 21 decades − 1 54 decades = 3 21 × 5 decades − 1 45 × 2 decades
× 5 × 2

= 3 150 decades − 1 180 decades

= 2 1105 decades − 1 180 decades

= 1 170 decades

3 21 decades − 1 54 decades = 1 170 decades

Encik Shamel has been staying in Taman Universiti 1 170 decades
longer than Encik Siva.

2 9 decades – 6 130 decades = decades years

3 decade = (130 × 10) years decade year Convert 9 decades to
10 8 decades 10 years.
8 10
= 3 years
90
−6 3

27

9 decades – 6 130 decades = 2 decades 7 years

160 4.3.1 (iv) • Instil moral values like the spirit of neighbourliness
and respect others.

warranty period
0.2 decade

3 B ased on the information given, calculate the difference
in warranty period between these two laptops.

0.3 decade − 0.2 decade = decade

0 . 3 decade warranty period
− 0.2 decade 0.3 decade

0. 1 decade

0.3 decade − 0.2 decade = 0.1 decade

The difference in warranty period between these two laptops is 0.1 decade.

4 Calculate the balance, in years, when 47 years is subtracted from
8.1 decades.

8.1 decades – 47 years = years 7 11

8.1 decades = (8.1 × 10) years 8 1 years
= 81 years − 4 7 years

3 4 years

8.1 decades – 47 years = 34 years

5 9.4 decades – 2 21 decades = decades years

9.4 decades = (9.4 × 10) years 8 14 69 years

= 94 years 9 4 years = 60 years + 9 years
− 2 5 years
2 21 (52 5 6 9 years = (60 ÷ 10) decades + 9 years
decades = × years
10)

1 = 6 decades 9 years

= 25 years

9.4 decades – 2 21 decades = 6 decades 9 years

1 2347

Use the above number cards to complete the
number sentence below.

6. decades − . decades = years

4.3.1 (iv) • Ask pupils to find the difference of expiry dates of food as a wise 161
4.3.2 (iv) consumer.

Centuries and decades

1 Calculate the age difference between
the two banknotes.
Age of
banknotes 1 century − 1 century = century
2 10
in 2021
1 century – 1 century = 1×5 century – 1 century
SPECIMEN 2 10 2×5 10

SPECIMEN =150 century – 110 century

=140÷÷22 century

=25 century

1 century − 1 century = 2 century
2 10 5

The age difference between the two banknotes is 2 century.
5

2 7 53 centuries – 4 centuries 8 decades = centuries decades

3 century = (53 × 2 decades Convert 1 century to 10 decades.
5 Then, add 10 decades and 6 decades
10)
to make 16 decades.
1

= 6 decades century decade
Therefore,
6 16

7 53 centuries = 7 centuries 6 decades. 76
−4 8

28

7 35 centuries – 4 centuries 8 decades = 2 centuries 8 decades

Complete this.
1 54 centuries – century = 12 decades

162 • Carry out subtraction activities involving centuries and decades
4.3.1 (v) using flash cards.
• Discuss the history and changes of banknotes in Malaysia.

3 C alculate the age difference in the production 1985 to 2008
of Proton Saga and Perodua Myvi models. (0.23 century)

0.23 century − 0.06 century = century 2005 to 2011
(0.06 century)
1 13

0. 2 3 century
− 0. 0 6 century

0. 1 7 century

0.23 century − 0.06 century = 0.17 century

The age difference in the production of
Proton Saga and Perodua Myvi models
is 0.17 century.

4 14.2 centuries – 3 centuries 9 decades = centuries decades

14.2 centuries = 14 centuries + 0.2 century century decade
= 14 centuries + (0.2 × 10) decades
= 14 centuries 2 decades 13 12

14 2
−3 9

10 3

14.2 centuries – 3 centuries 9 decades = 10 centuries 3 decades

5 6 110 centuries – 5.7 centuries = decades

6 110 centuries = 6 centuries + 1 century 5 11
10
6 . 1 centuries
= 6 centuries + 0.1 century − 5 . 7 centuries

= 6.1 centuries 0 . 4 century

0.4 century = (0.4 × 10) decades
= 4 decades

6 110 centuries – 5.7 centuries = 4 decades

How many centuries and decades are there if
2 51 centuries is subtracted from 4.1 centuries?

4.3.1 (v) 163
4.3.2 (v) • Instil moral value of patriotism by buying Malaysian products.

Centuries and years Find the age difference between
these two historical places.

1 Sultan Abdul Samad Building Fort Cornwallis, Pulau Pinang

Age of
Historical
Places in 2021

about 1 41 centuries 2 centuries 35 years

a 2 centuries 35 years − 1 41 centuries = century years

1 century = (41 × 25 years century year
4
100) 2 35
− 1 25
1
1 10
= 25 years

Therefore, 1 41 centuries = 1 century 25 years.

2 centuries 35 years − 1 41 centuries = 1 century 10 years

The age difference between these two historical places
is 1 century 10 years.

b H ow much older is the Kuala Lumpur
Railway Station, in years, compared
to the Sultan Abdul Samad Building?

1.3 centuries − 1 41 centuries = years In 2021, the Kuala

1.3 centuries = (1.3 × 100) years Lumpur Railway
= 130 years Station is about
1.3 centuries old.
2 10
1 41 centuries = (54 × 25 years
1 3 0 years
100) − 1 2 5 years

1 5 years

= 125 years

1.3 centuries − 1 41 centuries = 5 years

The Kuala Lumpur Railway Station is 5 years older than

the Sultan Abdul Samad Building.

164 4.3.1 (vi) • Discuss our national heritage and other historical places in
4.3.2 (vi) Malaysia. Pupils may conduct research on the age of historical
places in Malaysia in centuries and years as group projects.

1 Find the answers.

a 3 hour – 1 hour = hour b 0.5 hour – 0.45 hour = hour
4 2 day

c 5 day – 1 day = day d 0.25 day – 0.125 day =
8 3

e 7.75 years – 4.5 years = years

f 1 52 decades – 1 decade = decades
10

g 8.11 centuries – 6.7 centuries = centuries

2 Find the difference of duration.

a 5 hour – 13 minutes = minutes
6

b 1 hour 40 minutes – 0.95 hour = minutes

c 2 83 days – 1 day 2 hours = day hours

d 1.375 days – 4 hours = day hours

e 9 170 decades – 2 decades 3 years = years

f 8.1 decades – 27 years = decades years

g 2 centuries 4 decades – 1 51 centuries = decades

3 Solve these. acnesnwtueryr in34ceynetaurrsiefsroamnd5 y170eacersn.turies.

a Deduct 1
Give the


b Find the difference between 2.1 centuries and 6 centuries 9 years.

State the answer in years.

4 Find the answers.

a 454.5hoyuera–rs0–.151 15h2oyuera=rs minutes b 1 81 days – 0.875 day = hours
c d 9.1 decades – 6 130 decades


= years month = decades years

5 Complete the bridge map.

decades century decades years
as as

0.9 century – 1 century 3 21 centuries – 1.7 centuries 1 41 centuries – 0.9 century
5

4.3.1 165
4.3.2

SOLVE THE PROBLEMS

1 The diagram shows a packet

of curry paste and a packet of

potato crisps bought by Vimala.

Calculate the shelf life, in days, of

the curry paste. Date of manufacture:

9.12.2019
Expiry Date:
8.2.2021

Understand the Date of manufacture: 9.12.2019
problem Expiry date: 8.2.2021
Find out the shelf life, in days, of the curry paste.

Plan the date of shelf life expiry date
strategy manufacture

Solve 1 1 11
9.12.2019 to 31.12.2019
31 days – 9 days + 1 day = 223 ddaayyss
1.2.2021 to 8.2.2021 Number of days in 2020 = 3 3666 ddaayyss
Number of days in January 2021 = 3 31 ddaayyss

8 days – 1 day + 1 day = + 8 ddaayyss
Total days = 44228 ddaayyss

Check Use a calendar to check your answer.

The shelf life of the curry paste is 428 days.

This information is found on Date of
the packet of potato crisps above. manufacture:
17.02.2020
Calculate the shelf life, in days, Expiry date:
of the crisps. 17.08.2020

166 4.4.1 • Emphasise that the expiry date on food products indicates
the shelf life as this will help consumers make the right choice.

2 T he pictures show the duration of breakfast
40 minutes

time Zaidi spent on two activities

in the morning. Calculate the jogging
total duration of time, in hours
and minutes, Zaidi spent on 3 hour
both activities. 4

Understand the b43rehaokufar sstp. eFnintdotnhejogtogtainlgd.u4r0atmioninuotfetsimsepesnpteonnt on
problem
both activities.
Plan the
strategy 3 hour 40 minutes
4

Solve 3 hour + 40 minutes = hour minutes
4

Convert 3 hour to minutes. Total up. Convert 85 minutes to
4
3 (43 15 45 minutes hours and minutes.
4 hour = × minutes + 40 minutes
60) 85 minutes
85 minutes − 60 minutes 1 hour
1
25 minutes
= 45 minutes

Check 85 minutes 45 minutes = ( 45 ÷ 15 ) hour
− 40 minutes 60 ÷ 15

45 minutes = 3 hour
4
3
4 hour + 40 minutes = 1 hour 25 minutes

The total duration of time Zaidi spent on both activities is 1 hour 25 minutes.

Animated Film minutes Zaidi would like to watch
Animated Film minutes an animated film for 1.5 hours to
Animated Film minutes 2 hours. Which animated film would

he choose? Discuss.

4.4.1 • Guide pupils to solve problems using the Polya method based on 167
story cards.

3 T he table below shows the age of herbal tea leaves in three packets
given by Encik Tan to his neighbour.

Colour of the packet Age of herbal tea leaves
Green 10.75 years
Red
Brown 9 months more than the green packet

5 year less than the green packet
6

Calculate the age, in years and months, of the herbal tea leaves in the:

a red packet. b brown packet.

Solution Draw a

The green packet 10.75 years 9 months diagram.
The red packet
a

10.75 years + 9 months = years months

0.75 year = 3 year year month
4 10 9
3 (43 3
4 year = × months +9
12) 10 1 8

1 + 1 −12
11 6
= 9 months

Therefore, 10.75 years = 10 years 9 months

10.75 years + 9 months = 11 years 6 months

The age of the herbal tea leaves in the red packet is 11 years 6 months.

b 10.75 years − 5 year = years months
6
year month
5 year = (56 × 2 months Explain how
6 9 21 you check
12) the answer.
10 9
1 − 10

= 10 months 9 11

10.75 years − 5 year = 9 years 11 months
6

The age of the herbal tea leaves in the brown packet is 9 years 11 months.

168 • Provide various problem-solving questions involving daily life situations.
4.4.1 Demonstrate various strategies for the solution.
• Surf https://rb.gy/2rfhuf

4 In 2020, the Intellect Building and Harmony Building are 0.4 decade and
2 decades old, respectively. When would the age of the Harmony Building
be equal to 3 times the age of the Intellect Building?

Solution In 2020, the Intellect Building is 0.4 decade old.

Harmony Building is 2 decades old.

I use the trial and

error method. Age

The The Check

Intellect Harmony 0.5 decade
Building Building × 3

First Try 2021 0.5 decade 2.1 decades 1 .5 decades

Second Try 2022 0.6 decade
Third Try 2023 ×3
0.6 decade 2.2 decades 1 .8 decades
Fourth Try 2024
0.7 decade
×3
0.7 decade 2.3 decades 2. 1 decades

0.8 decade
×3
0.8 decade 2.4 decades 2.4 decades

The fourth try was accurate.

What are the other methods
to check the answer?

The age of the Harmony Building will be 3 times the age of the
Intellect Building in 2024.

The age difference between Aneka Building and
Harmony Building is 0.1 century. What is the age, in decades,

of the Aneka Building in 2020?

• Emphasise to pupils to check the answers using different calculation 169
4.4.1 strategies such as multiplication for repeated addition and division

for repeated subtraction.

5
1.15 centuries old

The total age of the two antique vases shown in the picture above is
318 years. What is the age, in centuries and years, of the blue and
white antique vase?

Solution

I use the working backward method.

+ 1.15 centuries = 318 years

Convert 1.15 centuries to years.
1.15 centuries = (1.15 × 100) years
= 115 years

5 years 10 years 100 years 115 years

208 218 years 318 years
years

203 years
203 years = 200 years + 3 years
= 2 centuries 3 years

I check using this method.

3 1 8 years 203 years = 200 years + 3 years
− 1 1 5 years = (200 ÷ 100) centuries + 3 years
= 2 centuries 3 years
203 years

2 centuries 3 years + 1.15 centuries = 318 years
The blue and white antique vase is 2 centuries 3 years old.

170 4.4.1 • Discuss various problem-solving strategies such as making tables
and simulations.

Solve the following problems. Soak the red beans Cooking

a T he time taken by Puan Aninah to prepare 50 minutes

the ingredients and to cook red bean

porridge is shown in the picture. What is the 1 32 hours
total duration, in hours and minutes, of the

time taken to get the meal ready?

b A filming began at 4:30 p.m. on Tuesday until 5:30 p.m. on Thursday.
Calculate the duration, in days and hours, of the filming.

c A school held an anti-drug campaign Anti-Drug
as shown in the picture. Calculate the
duration, in days, of the campaign. Campaign

3 February 2020
to 6 March 2020

d Historical Building Age in 2020
Masjid Jamek Kuala Lumpur 1.13 centuries
Royal Museum
Teluk Intan Leaning Tower 92 years
1.35 centuries

Based on the table of the age of historical buildings above,:

i calculate the age difference, in centuries, between
Masjid Jamek Kuala Lumpur and the Teluk Intan
Leaning Tower in Perak.

ii h ow much older, in years, is the oldest building compared

to the newest one?

e T he following is a conversation between two friends.

Navin I studied at SK Sentosa for 4 21 years and was
at SK Sepayan for 15 months.

Oh, I studied 0.75 year longer than Agus
you at SK Sentosa!

Based on the above conversation,:

i total up the duration, in years and months, Agus studied in both schools.

ii determine the duration, in months, Navin studied at SK Sentosa.

4.4.1 171

1 C alculate the duration of time for each of the activities.

a Start climbing on 20.5.2021,
at 10:00 a.m.

Finish climbing on 23.5.2021
at 1:00 p.m.

Give the answer in days and hours.

b Disaster Relief Fund c Food Preparation
Certificate Course
13 January 2021 to 5 March 2021
17 October 2021 to
Give your answer in days. 9 December 2021

Give your answer in days.

2 Convert the units of time.

a 1 hour = minutes b 1.2 hours = hour minutes
5
5
c 6 day = hours d 7.25 days = hours

e 2 1121 years = months f 1.5 years = year months

g 6 190 decades = decades years h 13.7 decades = years

i 3 21 centuries = decades j 24.1 centuries decade
= centuries
k 5 34 centuries = centuries years l 8.23 centuries = years

3 Calculate.

a 1 hour + 2 hour = hour b 1.5 days – 0.625 day = day
4 3
5
c 6 year + 33 months d 4 decades 2 years – 1.8 decades

= years months = years

e 1 decade 9 years + 8 21 decades f 7.7 centuries – 38 decades
= decades years = decades

g 3 centuries 12 years + 4 170 centuries h 320 years – 1.6 centuries
= years = century years

4.1.1, 4.2.1,
172 4.2.2, 4.3.1,

4.3.2

4 Complete the bridge map below.

minutes as hours as years

1 hour + 0.6 hour 2 day + 0.625 day 0.7 decade + 1 decade
10 3 2

5 Find the errors in these calculations and correct them.

a century year b decade year c century decade
67
4 13 15 10
+1 8
53 16 8 8 15
+1 6 −4 9
+1 − 1 0
37 11 1 95

6 Solve these.

a i 4.2 centuries + 18 decades = decades

ii 7.05 centuries − 106 years = centuries years

b Add 11 year and 2.5 years. Give the answer in months.
12

c Calculate the time difference, in centuries and years, between
6 170 centuries and 9.8 centuries.

7 The following are three cards; P, Q and R.

P 5 41 years Q 1.5 years R 32 months

a Convert the time on card R to years and months.

b S ubtract the time on card R from the time on card P. Give the
answer in months.

c H ow much more time, in years and months, of card P compared to
card Q?

4.2.1, 4.2.2, 173
4.3.1, 4.3.2

8 Solve the problems below.

a T he diagram below shows the process and time taken by Aley to
bake a cake.

preparation of mixing baking decorating
the ingredients 10 minutes 0.75 hour
1
1 hour 3 hour
2

i Calculate the total time taken, in hours, for preparing the ingredients
and decorating the cake.

ii W hat is the time difference, in minutes, between mixing and baking
the cake?

iii Calculate the duration, in hours and minutes, for baking and

decorating the cake.
b The duration of a television show is 2 41 hours including


advertisements of 20 minutes. Calculate the duration, in hours and

minutes, for the television show only.

c Historical Building Age in 2020

Atkinson Clock Tower 1.15 centuries
Kundasang War 58 years
Memorial
1 130 centuries
Masjid Jamek Sandakan

The table above shows the age of historical buildings in
Sabah in 2020.

i Calculate the difference of age, in years, between the
Atkinson Clock Tower and the Kundasang War Memorial.

ii Masjid Jamek Sandakan is 15 years older Is this statement true?

than the Atkinson Clock Tower. Prove it.

174
4.4.1

d A study tour to Malacca began on Thursday, 9:00 a.m. until
Saturday, 3:00 p.m. in the same week. Calculate the duration of
the tour, in days and hours.

e START END The calendar shows the effective dates of
2020 2020 Phase 1 of the Movement Control Order
(MCO) in Malaysia to break the chain of
18 31 COVID-19 transmission. How long, in
March March days, was the Phase 1 of the MCO?

f I n 2021, Nelly and Sudir are 8.5 years old and 19 years old respectively.

i H ow much older is Sudir than Nelly? Give the answer in years
and months.

ii In which year the age of Sudir be twice the age of Nelly?

g T he age difference between antique cars P and Q is 2 decades 7 years.
Antique car P is 5.8 decades old. How old, in decades and years, is
antique car Q?

h 0.7
century


Q decades R years

1 P 1
2 century 5
century century

Marsha is assigned to complete the above diagram. In the diagram,
the values P, Q and R are not given. The value in the box is the sum of
the two units of time in the circles connected to the box.

i Calculate the values of P, Q and R.

ii Is the sum of P and Q equal to 1 century 9 decades?
Show your calculation.

4.4.1 175

GROUP ACTIVITY

Tools/ Materials A4 papers, manila cards, glue, coloured pencils, pens,
Task scissors, recycled materials such as reading materials,
Internet

2 years 3 months

1 O n A4 paper, write down two units of 3 year + 1.5 years
time involving whole numbers, fractions, 4
or decimals that give the same number
of sum and difference. 3.5 years – 15 months

2 C ut and paste the A4 paper on a picture such 2 years 3 months
as pictures of animals that were drawn, pictures
from recycled materials, or from the Internet. 3 year + 1.5 years
4
3 P resent the completed work. Accept suggestions
for improvement from other groups. 3.5 years – 15 months

TIME

Mohan plucked some mangoes near the mansion,
But would not eat them as they were sour;
Let’s try to answer this question,
How many minutes are there in one and three
quarters of an hour?

When I am with my peers,
I am always full of cheers;
Two point two centuries and six years,
What is the difference, in years?

When Zaiton eats cakes and buns,
She is happy as can be;
Total up half a year and two months,
How many months will it be?

176 4.2.1 (i), 4.3.1,
4.3.2, 4.4.1

5 LENGTH, MASS, AND
VOLUME OF LIQUID

CONVERT UNITS OF LENGTH

Millimetres and centimetres This weighing tool was invented
using 9.2 cm thread and a 36 21 cm
1
clothes hanger.

a Convert 9.2 cm to mm.

9.2 cm = mm

9.2 cm = (9.2 × 10) mm

= 92 mm

b Convert 36 21 cm to mm. 9.2 cm = 92 mm

36 21 cm = mm 1 cm = 10 mm
× 10
36 21 cm = (723 × 5 mm 1
cm mm
10) 73
×5 ÷ 10
1
365
= 365 mm

36 21 cm = 365 mm

2 47 mm = cm 3 20 cm 6 mm = cm

in decimal 47 mm = (47 ÷ 10) cm 20 cm 6 mm = 20 cm + (160÷÷22) cm
= 4.7 cm
3
in 47 mm = 47 cm = 20 cm + 5 cm
fraction 10
= 20 53 cm
= 4 170 cm
3
47 mm = 4.7 cm or 4 170 cm 20 cm 6 mm = 20  5 cm

• Carry out simulation activities for measuring length, thickness of objects, 177
5.1.1 (i) and depths of water in cm and mm. Then, ask pupils to convert the unit
5.1.2 (i) to decimals or fractions.

• Recall methods of quick multiplication and division involving any
numbers by 10.

The width of this kite is 1.37 m.

Centimetres and metres

1 Convert 1.37 m to cm.

1.37 m = cm

1.37 m = (1.37 × 100) cm

= 137 cm

1.37 m = 137 cm

2 1 41 m = cm

Method 1 Method 2

1 41 m = 1m + 1 m 1 41 m = (45 × 100) cm
= (1 × 4 = (5 × ) cm
(41 25
100) cm + × cm = cm
100)
Does method 2 give
= 100 cm + 25 cm1 the same answer?

= 125 cm
1 41 m = 125 cm

3 3 9 cm = m 4 5 m 80 cm = m

39 cm = (39 ÷ 100) m 5 m 80 cm = 5 m + (80 ÷ 100) m

= 0.39 m = 5 m + 0.8 m

39 cm = 0.39 m = 5.8 m

5 m 80 cm = 5.8 m

1 m = 100 cm 5.8 m is equal to 5 45 m. Prove it.
× 100

m cm

÷ 100

178 5.1.1 (ii) • Encourage pupils to appreciate traditional games such as wau, gasing,
5.1.2 (ii) and congkak.

• Use various methods to state the relationships between units involving

fractions and decimals.

Metres and kilometres Penang Bridge
International Marathon
1 C onvert 42.195 km to m.
42.195 km = m Overall distance 42.195 km

42.195 km = (42.195 × 1 000) m Date: 24 November 2019
Starting time: 1:30 a.m.
= 42 195 m (Men and Women Open, and Veteran)
Qualifying time: 7 hours
Starting point: Queensbay Mall Parking Lot

42.195 km = 42 195 m

2 7  38 km = m 3 10 300 m = km

7 83 km = 7 km + 3 km 10 300 m = (10 300 ÷ 1 000) km
8
= 10.3 km
= (7 × 1 000) m +
=10 130 km
(38 × 1 125 m

000)

1 10 300 m = 10.3 km or
= 7 000 m + 375 m

7 83 km = 7 375 m 10 130 km

4 68 km 4 m = km 1 km = 1 000 m
× 1 000
68 km 4 m = 68 km + ( 1 4 ) km
000 km m

= 68 km + 0.004 km ÷ 1 000

= 68.004 km

68 km 4 m = 68.004 km

1 km 3 km
2 4

0 375 m P Q R 1 000 m

State the value of Q in fractions.

5.1.1 (iii) • Encourage pupils to use various strategies during multiplication or division 179
5.1.2 (iii) such as shifting the decimal point or cancellation.

1 Convert the measurements below to the required units.

a 3.1 cm = mm b 7 21 cm = mm c 56 mm = cm
cm f 10 34 m = cm
d 8 cm 4 mm = cm e 0.19 m =
km
g 37 cm = m h 5 km 2 m = km i 2 043 m =

2 State the answers in decimals.
a 908 mm = cm b 24 m 6 cm = m c 79 cm = m
d 45 cm 3 mm = cm e 6 005 m = km f 18 km 14 m = km

3 State the answers in fractions. km
a 25 mm = cm b 4 cm 1 mm = cm c 920 cm = m
d 6 m 75 cm = m e 1 300 m = km f 50 km 600 m =

GET TO KNOW ME Activity card

Tools/Materials activity cards, pens, Height Shoe School Distance
sole bag from home
Measurement width to school
length
measuring tapes,

rulers, manila mm/cm/m/km

cards, photos fraction or
decimal unit

Participants in pairs Results

Task Name: Kamini a/p Muthu

1 C arry out measurement activity and Height : 139 cm = 1.39 m
complete the activity card. Shoe sole length: 18.6 cm
School bag width: 20.3 cm
2 Copy your friend’s details on the manila
card and paste the photo. Distance from home to school: 3 170 km

3 C ompile everything in a scrapbook.

180 5.1.1 • Carry out a quiz to be answered spontaneously. For example, 3.5 cm
5.1.2 1
in fraction is 3 2 cm.

• Guide pupils to use Google Maps to find the distance from home to school in

the Smart Trail” activity.

ADDITION OF UNITS OF LENGTH Uranus
18.4 cm
1 a Calculate the total length of the strings
of the Earth and Uranus replicas. Earth
26.3 cm

26.3 cm + 18.4 cm = cm Mercury

1 30 21 cm

2 6.3 cm
+ 1 8.4 cm

4 4.7 cm

26.3 cm + 18.4 cm = 44.7 cm

The total length of the strings of the Earth and
Uranus replicas is 44.7 cm.

b Total up the length, in mm, of the strings of the Earth,

Uranus, and Mercury replicas.

26.3 cm + 18.4 cm + 30 21 cm = mm

30 21 cm = 30 cm + 1 cm 11
2
2 6.3 cm
= 30 cm + 0.5 cm 1 8.4 cm 75.2 cm
+ 3 0.5 cm = (75.2 × 10) mm
=30.5 cm 7 5.2 cm

26.3 cm + 18.4 cm + 30 21 cm = 752 mm = 752 mm

The total length of the strings of the Earth, Uranus, and Mercury

replicas is 752 mm.

2 74 cm + 1.08 m + 2 43 m = m

74 cm = (74 ÷ 100) m 2 43 m = 11 m 2.7 5m
=0.74 m 4
4 1 1.0 0m
=2.75 m −8
30
74 cm + 1.08 m + 2 43 m −2 8
= 0.74 m + 1.08 m + 2.75 m
20
= 4.57 m −20

0

74 cm + 1.08 m + 2 43 m = 4.57 m

• Ask pupils to make sure that all the measurements have been 181
converted to the same unit and same form (fraction or decimal)

5.1.3 before performing addition.
• Carry out an activity of adding all the sides of various triangular
shapes involving measurements in fractions and decimals.

Hani’s 8 53 km flower shop

3 Calculate the distance, in m, home

from Hani’s home to the bird 3 km 20 m 4.701 km
park through the flower shop

and restaurant. 11 km 65 m 2.9 km bird
8 35 km + 3 km 20 m + 2.9 km = park
m
restaurant

8 35 (453 200 3 km 20 m = 3 km + 20 m

km = × 1 000) m = (3 × 1 000) m + 20 m

1 = 3 000 m + 20 m

= 8 600 m = 3 020 m

2.9 km = (2.9 × 1 000) m 1 State the shortest
= 2 900 m distance to the
8 600 m bird park from
3 020 m Hani’s home.
+ 2 900 m

1 4 520 m

8 35 km + 3 km 20 m + 2.9 km = 14 520 m
The distance from Hani’s home to the bird park
through the flower shop and restaurant is 14 520 m.

1 Add the measurements below according to the required units.

a 37.9 cm + 4.8 cm = cm b 6.7 cm + 33.9 cm = mm

c 20 51 cm + 7.6 cm = cm d 81.4 cm + 65 cm = mm

e 80 cm + 2.04 m + 1 m = m f 31 45 m + 103 cm + 18.9 m = cm
2 m
g 11 81 km + 45.7 km = km h 50.207 km + 48 130 km + 30 m =

2 Add 78.3 cm and 27 cm. Give your answer in mm.

3 Based on the cards given, find 23 52 km

the total distance in: 9.012 km 4 km 960 m

a km bm

182
5.1.3 • Vary the questions such as calculating the sum of numbers.

SUBTRACTION OF UNITS OF LENGTH

1 a What is the difference in height 62.7 cm 3 cm
between Robot R and Robot S? 54.9 cm 5

62.7 cm – 54.9 cm = cm shorter

11 than
5 1 17
Robot S
62.7 cm
– 54.9 cm R ST

7.8 cm

62.7 cm – 54.9 cm = 7.8 cm
The difference in height between Robot R and Robot S is 7.8 cm.

b C alculate the height, in mm, of Robot T.

54.9 cm – 3 cm = mm
5

54.9 cm – 3 cm = (54.9 × 10) mm – (53 × 2 mm
5
10)

= 549 mm – 6 mm 1

= 543 mm

54.9 cm – 3 cm = 543 mm
5

The height of Robot T is 543 mm.

2 2.07 m – 16 cm – 4 m = m
5
First, convert the measurement in
16 cm = (16 ÷ 100) m 0.8 m decimal m. Then, subtract.
= 0.16 m 5 4.0 m
1 10
−0
40 2.07 m
–0. 1 6 m
−4 0
0 1.91 m
–0.80 m

2.07 m – 16 cm – 4 m = 1.11 m 1.1 1 m
5

• Encourage pupils to subtract by finding the balance or difference 183

5.1.4 of length of an object.
• Ask pupils to carry out the required conversion of unit of length

according to the questions.

3 How much longer is the Penang Bridge compared
to the Terengganu Drawbridge?

13.5 km – 638 m = km

14 9

638 m = (638 ÷ 1 000) km 2 410 10

= 0.638 km 1 3 . 5 0 0 km
– 0 . 6 3 8 km

Terengganu Drawbridge 1 2 . 8 6 2 km

638 m

13.5 km – 638 m = 12.862 km

The length of the Penang Bridge is 12.862 km

longer than the length of the Terengganu
Penang Bridge Drawbridge.

13.5 km

4 90 87 km – 34.3 km – 1 180 m = m

90 87 km = 90 km + 7 km 34.3 km = (34.3 × 1 000) m
= (90 × 1 8 = 34 300 m
(87 125
000) m + × 1 m 8 10 4 17
000)
90 87 5 m 56 57 5
= 90 000 m + 875 m1 – 34 30 0 m – 1 180 m
m

= 90 875 m 56 57 5 m 55 395 m

90 87 km – 34.3 km – 1 180 m = 55 395 m

Emperor Penguin’s height: 1.  m – 1 m = 1.15 m

The number on is the same.
What is the number?

Calculate these. cm b 67.8 cm – 2 190 cm = mm
a 53.1 cm – 12.9 cm =

c 18 43 km – 6.509 km = km d 4.15 m – 72 cm – 1 35 m = m

e 30 1 m – 340 cm – 25.7 m = cm f 26 34 km – 8 km 85 m – 9.27 km = m
2

184 5.1.4 • Carry out a quiz in groups involving subtraction up to three
measurements of length.

MULTIPLICATION OF UNITS OF LENGTH

1 a What is the width of
the decorative frame?

6 × 2.8 cm = cm Stay Think Effort is width
2.8 cm Positive the Key to
4 FOCUSed! Be
Positive Success
2. 8 cm
×6

1 6. 8 cm

6 × 2.8 cm = 16.8 cm 1.9 cm

The width of the decorative frame is 16.8 cm.

b Calculate the length, in mm, of the decorative frame.

14 × 1.9 cm = mm 3 Calculate the
length and
1 9 mm width of each
motivational
1.9 cm = (1.9 × 10) mm × 14 card on the
1 76 frame above.
= 19 mm
+1 90

14 × 1.9 cm = 266 mm 2 6 6 mm

The length of the decorative frame is 266 mm.

2 56 × 7 43 m = cm

Method 1 Method 2 7 34 m = 7m + 3 m
= (7 × 4
7 43 14 31 (34 25
56 × m = × 4 m 100) cm + x cm
56 100)

1 1
= 700 cm + 75 cm
= 434 m

= (434 × 100) cm = 775 cm
= 43 400 cm
32
43

7 7 5 cm

× 56

111

56 × 7 34 m = 43 400 cm 4650
+ 38750

4 3 4 0 0 cm

• Use various daily life situations involving multiplication such as 185
5.1.5 finding the length of joined benches or tables.

• Instil other moral values such as perseverance and diligence.

3 Calculate the total distance, in m, that Aiman travelled to
school for 5 days on a round-trip.
10 × 2.735 km = m

10 × 2.735 km = 10 × (2.735 × 1 000) m 2.735 km
= 10 × 2 735 m
= 27 350 m

10 × 2.735 km = 27 350 m

The total distance that Aiman travelled to school for
5 days on a round-trip is 27 350 m.

4 100 × 48 21 m = km 5 1 000 × 19 45 cm = m

1 m = 0.5 m 4 cm = 0.8 cm
2 5

100 × 48 21 m = 100 × 48.5 m 1 000 × 19 54 cm = 1 000 × 19.8 cm
= 4 850 m = 19 800 cm

= (4 850 ÷ 1 000) km = (19 800 ÷ 100) m

= 4.850 km = 198 m

100 × 48 21 m = 4.85 km 1 000 × 19 45 cm = 198 m

1 Multiply. b 6 × 9 43 cm =

a 8 × 4.39 cm = cm d 25 × 7.44 m = mm
f 70 × 10 21 m = km
c 13 × 7 51 cm = m km

e 42 × 18.05 km = km

2 Complete these.

a 0.2 km m b 8.3 cm mm
cm cm
100 × 1 m = km 1 000 × 2 51 m = m
4

1.567 km 0.046 km

186 5.1.5 • Drill multiplication of measurements of length using charts or
picture cards.

DIVISION OF UNITS OF LENGTH

1 What is the thickness of a 10 sen coin?
12 mm ÷ 8 = mm

1 . 5 mm 12 mm

8 1 2 . 0 mm
−8
40
−4 0
0

12 mm ÷ 8 = 1.5 mm
The thickness of a 10 sen coin is 1.5 mm.

2 45.18 cm ÷ 9 = mm  3 3 51 m ÷ 16 = cm
Step 1
Step 1
5 . 0 2 cm 3 51 m = ( 16 × 20 cm
5
9 4 5 . 1 8 cm 100)
−4 5
01 1
−0 = 320 cm
18
− 18 Step 2
0 2 0 cm

Step 2 1 6 3 2 0 cm
–3 2
5.02 cm = (5.02 × 10) mm 00
= 50.2 mm –0
0
45.18 cm ÷ 9 = 50.2 mm
3 51 m ÷ 16 = 20 cm
Can you convert to mm unit
first, then divide? Discuss.

5.1.6 • Carry out simulation activities such as finding the thickness of 187
a book from a stack of similar books.

4 Calculate the distance, in m, of the

resurfaced road in 1 hour. We took 10 hours to resurface

2 41 km ÷ 10 = m 2 1 km of road.
4

2 41 km ÷ 10 = 9 km ÷ 10
4

= (2.25 × 1 000) m ÷ 10

= 2 250 m ÷ 10

= 225 m

2 41 km ÷ 10 = 225 m

The distance of the resurfaced road

in 1 hour is 225 m.

5 238.9 km ÷ 100 = m 6 30 m 72 cm ÷ 1 000 = cm
30 m 72 cm = (30 × 100) cm + 72 cm
238.9 km ÷ 100 = 2.389 km = 3 000 cm + 72 cm
= 3 072 cm
= (2.389 × 1 000) m
3 072 cm ÷ 1 000 = 3.072 cm
= 2 389 m
30 m 72 cm ÷ 1 000 = 3.072 cm
238.9 km ÷ 100 = 2 389 m

1 Divide. cm b 83 54 mm ÷ 10 = mm
a 0.12 cm ÷ 3 = d 25 81 km ÷ 25 = m

c 56.64 m ÷ 16 = cm

2 Complete these. km
a 48.3 km ÷ 10 = m
b 48.3 km ÷ 100 =

3 Divide the following. State the answer in m.

a 3.672 km by 18. b 32 m 10 cm by 100.

188 5.1.6 • Drill division of measurements of length using suitable materials
such as pieces of thread, string, and ribbon.

CONVERT UNITS OF GRAM AND KILOGRAM

1 a C onvert 1.8 kg to g. kg

1.8 kg = g
1.8 kg = (1.8 × 1 000) g
= 1 800 g
1.8 kg = 1 800 g

b 2 34 kg = g 1.8 kg 2 43 kg

Method 1 Method 2

2 34 kg = (141 × 250 g 2 43 kg = 2 kg + 3 kg
4
1 000)

1 250 (43 250
= 2 750 g × 1 1
= (2 × 1 000) g + × 1 000) g

250 = 2 000 g + 750 g1

+2 5 0 0

2 750 = 2 750 g

2 34 kg = 2 750 g

2 3.07 kg = kg
3.07 kg = 3 kg + 0.07 kg

= 3 kg + kg

= kg 1 kg = 1 000 g
× 1 000
Is 2 51 kg equal to 2 200 g? Prove it. kg g

÷ 1 000

5.2.1 • Pupils carry out the activity of converting unit of kg to g or vice versa 189
based on the printed mass on product packaging.

3 Convert 6 900 g to kg.
6 900 g = kg

6 900 g = (6 900 ÷ 1 000) kg in fraction 6 900 g = ( 6 900 ) kg
1 000
in decimal
= 6.9 kg = 69 kg
10

6 900 g = 6.9 kg or 6 190 kg = 6 190 kg

4 Convert 5 kg 800 g to kg. State the answer
in fraction.
5 kg 800 g = kg
5 kg 800 g = 5 kg + 800 g 5. 25 kg = 5  8 kg
= 5 kg + (800 ÷ 1 000) kg Find the possible
= 5 kg + 0.8 kg value of and .
= 5.8 kg
5 kg 800 g = 5.8 kg

1 Complete these.

a 0.01 kg = g b 6 53 kg = g c 4 250 g = kg
g f 7 kg 2 g = kg
d 8 kg 400 g = kg e 3 190 kg =

2 State the answers in decimal.

a 5 130 g = kg b 65 g = kg

3 State the answers in fraction.

a 500 g = kg b 7 125 g = kg

190 5.2.1 • Carry out a quiz on converting units of mass involving fractions
and decimals.

ADDITION OF UNITS OF MASS

1 The mass of a T otal up the mass of the
cabin baggage bag and the present.

should not 3.505 kg + 0.48 kg = kg

exceed 7 kg. 3.505 kg
+ 0.480 kg
3.505 kg
3.985 kg
3 81 kg 270 g 0.48 kg
3.505 kg + 0.48 kg = 3.985 kg

The total mass of the bag and
the present is 3.985 kg.

b Calculate the total mass, in kg, of clothes and a pair of sports shoes.

3 81 kg + 270 g = kg

Convert 3 81 kg and 3 81 kg = 25 kg 270 g = 270 kg
270 g to decimal kg 8 1 000

first. 3 . 1 2 5 kg = 0.27 kg

8 2 5 . 0 0 0 kg 3 81 kg + 270 g
−2 4 = 3.125 kg + 0.27 kg
10
−8 = 3.395 kg
20
− 16
40
−40
0

3 81 kg + 270 g = 3.395 kg Cabin baggage is a
The total mass of clothes and a pair of sports clothes bag and other
shoes is 3.395 kg. items that are carried
along or placed in the
State the items that can be put compartment of an
into the bag as cabin baggage. aeroplane.

5.2.2 • Carry out simulation activities such as weighing every product or tool using 191
a digital weighing scale to find the total mass.

2 6.73 kg + 1 080 g + 4 190 kg = kg

6.73 kg + 1 080 g + 4 190 kg = 6.73 kg + 1 080 kg + 4.9 kg 11
1 000
6 . 7 3 kg
= 6.73 kg + 1.08 kg + 4.9 kg 1 . 0 8 kg
+ 4 . 9 0 kg
= 12.71 kg
1 2 . 7 1 kg
6.73 kg + 1 080 g + 4 190 kg = 12.71 kg

3 7 kg + 4.305 kg + 945 g = g
8

7 kg + 4.305 kg + 945 g = (87 × 1 000) g + (4.305 × 1 000) g + 945 g
8

= g + g + g

= g

1 Calculate. b 3 kg + 760 g = g
a 7.42 kg + 0.845 kg = kg 5
c 12 21 kg + 4.8 kg + 370 g = kg d 80 g + 6 41 kg + 9 kg =
g
2

kg Add the mass, in g, for
pineapple and papaya.

1.608 kg 1.4 kg

3 Calculate the total 1 kg 217.5 g 0.25 kg
mass, in g, for all 8
three packets of the
wafer as shown in
the pictures.

192
5.2.2 • Drill addition of mass using question cards or supermarket pamphlets.