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7/28/2019 4 Decimals (Pg 56-86)
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WAJA MATHS YEAR 4 JPN PERAK
1.Name and write decimals with one to two decimal places.
56
10. Divide decimal of one decimal
place and two decimal places by
a) one-digit number
b) 10
11. Divide decimals by a whole numberwith the dividend value of up to
two decimal places.
12. Solve problems involving division
of decimals
8. Multiply any decimal of one
decimal place and two
decimal places with
a) one-digit number
b) 10, 100, and 1 000
9. Solve problems involving
multiplication of decimals.
1. Name and write decimals with a) one decimal place b) two decimal places
2. Recognise the place value of a) tenths b) hundredths c) tenths and hundredths
3. Convert fractions to decimals of a) tenths b) hundredths c) tenths and
Hundredths vice versa
4. Add any two to four decimals of
one decimal place and two decimal
places involving
a) decimals only c) mixed decimals
b)Whole numbers and decimals
5. Solve problems involving addition
of decimal numbers.
6. Subtract one to two decimals of
one decimal place and two
decimal places involving
a) decimals only
b) mixed decimals
c) Whole numbers and decimals
(mixed decimals)
7. Solve problems involving
Subtraction of decimal.
Learning Outcomes
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WAJA MATHS YEAR 4 JPN PERAK
Example 1.
Practise reading the decimal numbers below
1. 0.3 - zero point three
2. 0.6 - zero point six
3. 0.89 - zero point eight nine
4. 15.03 - fifteen point zero three
5. 23.48 - twenty-three point four eight.
6 0.4 - ________________________
7. 0.01 - ________________________
8. 4.3 - ________________________
9. 47.28 - ____________________________
Example 2
Write down the number ofdecimal places for each number.
1. 0.8 2. 6.5 8
Number Total number ofdecimal places
6.8 1 decimal place
46.71 2 decimal places
0.3
5.5
23.09
57
Tips5.26 - is read as five point two six
The dot is known as the decimal point.
The number of decimal places of a decimal is thenumber of digits after the decimal point.
1 decimal place 2 decimal places
Lets try
this !!!
After the decimal point read one number at a time
TIPS7 - WHOLE NUMBERA whole number canbe a decimal number
7.0 - 1 decimal place7.00 - 2 decimal
Lets try
this !!!
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WAJA MATHS YEAR 4 JPN PERAK
Exercise 1 Write the decimals in numerals or in words.
1
Zero point five 2 Zero point nine
3
One point seven 4 Three point eight
5
Eleven point one 6 Zero point nine one
7
Zero point zero five 8 Twenty-four point two six
9
Forty-two point three three 10 Seventy point three nine
1
1
0.6 1
2
0.7
1
3
6.9 1
4
8.8
1
5
5.1 1
6
3.07
1
7
62.35 1
8
50.05
58
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WAJA MATHS YEAR 4 JPN PERAK
1
9
13.28 2
0
76.86
2. Recognise the place value of : a) tenths b) hundredths c) tenths and hundredths.
Example 1.
The place values and digit values for the decimal 247.38 are as follows.
Whole Number Decimal
point
Decimal Number
Place Value Hundreds Tens Ones Tenths Hundredths
2 4 7 . 3 8
Digit Value 200 40 7 10
3
=0.3
100
8
= 0.08
State the place values of the underlined digit.
1. 14.3 tens (refer the table above)
2. 3.9 ones (refer he table above)
3. 8.75 hundredths (refer the table above)
4. 8.9 tenths (refer the table above)
5. 28.17
6 35.23
59
Points to note:Each digit in a decimal has its
own place value and digitvalue.
TIPSThe place value after thedecimal point ended with
ths
PLACE VALUE OF DECIMAL NUMBERS
A point separates
whole numbers anddecimal numbers
Lets try this !!!
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WAJA MATHS YEAR 4 JPN PERAK
7. 15.06
Exercise 2
State the place values of the underlined digits.
1. 0.27 2. 6.12
3. 2.47 4. 0.05
5. 51.31 6. 20.20
7. 45.13 8. 47.89
9. 13.98 10
.
37.33
60
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WAJA MATHS YEAR 4 JPN PERAK
3. Convert fractions to decimals of: a) tenths b) hundredths c) tenths and hundredths and vice versa.
Example 1.
1.10
1= 0.1
2.10
7= 0.7
3.10
3= 0.3
4.10
4=
5.
10
6=
6.10
8=
7.100
3= 0.03
8. 100
7
= 0.07
9.100
19= 0.19
10.100
8=
11100
4=
61
Convert fractions to decimal number.
POINTS TO NOTEA fraction with a denominator of
10 is equivalent to a decimalwith one decimal place.
TIPSDenominator 10
One decimal place
Lets try this !!!
POINTS TO NOTEA fraction with a denominator of100 is equivalent to a decimal
with two decimal places.
TIPSDenominator 100
two decimal places
Lets try this !!!
1 zero
1digit after thedecimal place
2 zeros
2 digits after thedecimal place
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WAJA MATHS YEAR 4 JPN PERAK
12.100
23=
Example 2.
1. 0.3 =10
3
2. 0.1 =10
1
3. 0.7 =
4. 0.9 =
5. 0.3 =
6. 0.13 =100
13
7. 0.33 =100
33
8. 0.57 =
9. 0.08 =
10. 0.42 =
62
Convert decimals number to fractions.
Lets try this !!!
Lets try this !!!
1 digit after
the decimal point
1 zero
2 digits afterthe decimal place
2 zeros
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WAJA MATHS YEAR 4 JPN PERAK
Exercise 3
Convert the following fractions to decimal and vice versa.
1.
10
5=
210
9=
3
100
9=
4100
17=
5 100
47
= 6 0.3 =
7 0.7 = 8 0.91 =
9. 0.56 = 10
.
0.02 =
63
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WAJA MATHS YEAR 4 JPN PERAK
4.. Add any two to four decimals of one decimal place and two decimal places involving
a) decimals only b) whole numbers and decimals c) mixed decimals
Example 1
64
0.6 + 0.1
0.6
+ 0.1
0.7
8 + 0.5
8.0
+ 0.5
8.5
12.3 + 6.6 + 2.41 112.3
6.6+ 2.4
21.3
Arrange in vertical form
according to its place values
Decimal points must be in a
straight line.
Arrange in vertical form.
Decimal points must be in
a straight line.
Arrange in vertical form.
Decimal points must be in
a straight line.
regroup if necessary .
Lets
trythis!!
!
0.7 + 0.2 6 + 2.8 0.2 + 5.3 + 2.9
Arrange the whole number
to one decimal place.
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WAJA MATHS YEAR 4 JPN PERAK
Example 2
65
0.4 + 0.78
0.04
+ 0.78
0.82
3 + 0.15 + 0.08
3.00
0.15
+ 0.08
3.23
11.1+ 6.6 + 72.41 111.1
6.6+72.4
90.1
Arrange in vertical form
Decimal points must be in a
straight line
Arrange in vertical form
Change the whole number
to two decimal places
Decimal points must be in
a straight line
Arrange in vertical form
Decimal points must be in
a straight line
Regroup if necessary.
3.65 + 8.26 20 + 12.63 10.29 + 5.44 + 25 2.9
Lets try this !!!
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WAJA MATHS YEAR 4 JPN PERAK
Exercise 4
Add the following.
1 0.5 + 0.3 = 2 13 + 0.8 =
3 42.3 + 5.6 + 0.7 4 71.4 + 6.51 =
66
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WAJA MATHS YEAR 4 JPN PERAK
5 12.46 + 8.17 = 6 17 + 0.7 + 7.82 =
5. Solve problems involving addition of decimal numbers.
1. .1
2. 0.1
3. 0.05
4. 24.26
5. 42.33
6. 70.39
1. or point seven
2. six point nine
3. eight point eight
4. five point one
5. three point zero seven
6. sixty-two point three five
7. fifty point zero five
8. thirteen point two eight
9. seventy-six point eight six
1. 1 decimal place2. 1 decimal place
3. 2 decimal places
4. 2 decimal places
5. 2 decimal places
6. 1 decimal place
2.
3. tenths
4. hundredths
67
EXAMPLE HOW TO SOLVE
EXAMPLE 1
Mazlan weighs 30.4 kg and Wan weighs 0.7 kg more
than Mazlan. What is Wans weight?
Step 1 :
Read and understand question. As you read, underline the
key words.
Mazlan weighs 30.4 kg and Wan weighs 0.7 kgmore than Mazlan. What is Wans weight?
Step 2 :
Write the operation / formula of the keywords signify.
Mazlan weighs 30.4 kg and Wan weighs 0.7 kg
( + )
more than Mazlan. What is Wans weight?
Step 3 : Add
.
0.7 kg + 30.4 kg
0.7 kg
+ 30.4 kg
31.1 kg Answer : 31.1 kg
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WAJA MATHS YEAR 4 JPN PERAK
Exercise 5
Solve the problems
1
.
A pail holds 2.5lof liquid and a basin holds
3.5 lof liquid. Find the total volume of liquid, in litres, in the two containers.
2
.
.Bottle A contains 1.5 lof syrup. Bottle B contains 2.3 lof syrup and bottle C
contains 0.25 lof syrup. What is the total volume of syrup in the three bottles ?
68
Note : + and are on the same scale. So calculate
as in the order given.
Step 2: Step 3:
RM8000 RM9254
+ RM1254 RM5555RM9254 RM3699
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WAJA MATHS YEAR 4 JPN PERAK
3
.
The length of three sticks is 3.9 m, 0.87 m and 1.57 m. What is their total length?
6. Subtract one to two decimals of one decimal place and two decimal places involvinga) decimals only b) mixed decimals c) whole numbers and decimals (mixed decimals).
Example 1
69
0.8 0.4
0.8
0.40.4
9 0.58 10
9.0
0.5
8.5
0.7 0.3 0.1
0.7 0.4 0.3 0.1
0.4 0.3
Arrange in vertical form
according to its place values.
Decimal points must be in a
straight line.
Arrange in vertical form
according to its place values.
Change the whole number
to one decimal place.(ex.9 = 9.0 )
Decimal points must be in
a straight line.
regroup if necessary
Arrange in vertical form
according to its place values.
Decimal points must be in
a straight line.
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WAJA MATHS YEAR 4 JPN PERAK
Example 2
70
2.8 - 0.3 6 - 2.8 9 - 0.5 - 1.4
9.71 - 5.476 11
9.71 5.47
4.24
3.78 2.35
3.78
2.35
1.43
82.08 14.2 9.65 17
82.08 67.88 14.20 9.60
67.88 58.28
Arrange in vertical form
according to its place values.
Decimal points must be in a
straight line
regroup if necessary
Arrange in vertical form
according to its place values.
Decimal points must be in
a straight line
regroup if necessary
Arrange in vertical form
according to its place values.
Decimal points must be in
a straight line.
regroup if necessary
Lets try this !!!
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WAJA MATHS YEAR 4 JPN PERAK
Exercise 6
Subtract the following.
1 0.9 0.3 = 2 19.3 0.8 =
3 20 6.8 3.7 = 4 9 0.57 =
71
0.9 - 0.1 65.9 - 63 16.05 - 3.5 - 2.88
Lets try this!!!
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WAJA MATHS YEAR 4 JPN PERAK
5 7.64 1.58 0.6 = 6 17 3.7 11.11 =
7. Solve problems involving subtraction of decimal numbers.
7. .1
8. 0.19. 0.05
10. 24.26
11. 42.33
12. 70.39
10. or point seven
11. six point nine
12. eight point eight
13. five point one
14. three point zero seven
15. sixty-two point three five16. fifty point zero five
17. thirteen point two eight
18. seventy-six point eight six
7. 1 decimal place
8. 1 decimal place
9. 2 decimal places
10. 2 decimal places
11. 2 decimal places
12. 1 decimal place
5.
72
EXAMPLE HOW TO SOLVE
EXAMPLE 1
The length of a stick is 7.5 m. If 3.95 m of the
stick is cut off, what is the length of the stickremains?
Step 1 :
Read and understand question. As you read underline the
keywords.
The length of a stick is 7.5 m. If 3.95 m of the stick is cut
off, what is the length of the stick remains?
Step 2 :
Write the operation / formula the keywords signify.
The length of a stick is 7.5 m. If 3.95 m of the stick is
()
cut off, what is the length of the stick remains ?
Step 3 : Minus.
7.5m 3.95m
7.50 m
- 3.95 m
3.55 m
Answer : 3.55 m
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WAJA MATHS YEAR 4 JPN PERAK
6. tenths
7. hundredths
Exercise 7
Solve the problems.
1 Yanti bought 10 m of cloth to sew dresses. She used up 8.9 m for her twin
daughters dresses. How much cloth is left?
2 Joseph bought 1.3 lof fresh milk. He drank 0.5 lof it.
What was the volume of milk left?
73
Note : + and are on the same scale. So calculate
as in the order given.
Step 2: Step 3:
RM8000 RM9254
+ RM1254 RM5555
RM9254 RM3699
Points to notePut a zero to obtain
2 decimal places.
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WAJA MATHS YEAR 4 JPN PERAK
3 Asmah has a piece of string 14 m long. She cut two pieces, one 3.5 m and the other
5.6 m long. How long is the remaining string?
8. Multiply any decimal of one decimal place witha) one-digit number, b) 10, 100 and 1 000.
Example 1.
Example 2
74
5 6.7 = 33.53
6.7
5
33.5
1. Arrange in vertical form.
2. Place the multiplier below
the last decimal place.
3. Multiply one digit at a time
from right to left.
4. Regroup if necessary.
5. Put the decimal point
according to the decimal
place.
7 2.4 =
Lets try this !!!
1. Arrange in vertical form.
2. Place the multiplier below
the last decimal place.3. Multiply one digit at a time
from right to left.
4. Regroup if necessary.
5. Put the decimal point
according to the decimal
place.
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WAJA MATHS YEAR 4 JPN PERAK
Example 3
75
5 0.67 = 4.024
0.67
6
4.02
7.8 10 = 78Move the decimal point one
place to the right.
4 0.29 =
3.7 10 = 5.71 100 = 9.197 1000 =
Lets try this !!!
Lets try this !!!
Lets try this !!!
2.3 9 100 = 239
9.5 1 6 1000 = 9 516
Move the decimal point two
places to the right.
Move the decimal point three
places to the right.
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WAJA MATHS YEAR 4 JPN PERAK
Exercise 8
Multiply.
1 0.3 7 = 2
31.6 10 =
3 16.8 100 = 4 6.2 1 000 =
76
3.03 10 9.22 100 48.3 1 000
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WAJA MATHS YEAR 4 JPN PERAK
5 4.47 2 = 6 0.45 10 =
7 7.34 100 = 8 8.48 1 000 =
9. Solve problems involving multiplication of decimal numbers.
13. .114. 0.1
15. 0.05
16. 24.26
17. 42.33
18. 70.39
19. or point seven
20. six point nine
21. eight point eight
22. five point one
23. three point zero seven24. sixty-two point three five
25. fifty point zero five
26. thirteen point two eight
27. seventy-six point eight six
13. 1 decimal place
14. 1 decimal place
15. 2 decimal places
16. 2 decimal places
17. 2 decimal places
18. 1 decimal place
77
EXAMPLE HOW TO SOLVE
EXAMPLE
The mass of a packet of biscuits is 1.25 kg. What is
the total mass of 3 packets of biscuits ?
Step 1 :
Read and understand question. As you read underline the
key words.
The mass of a packet of biscuits is 1.25 kg. What is the
total mass of 3 packets of biscuits ?
Step 2 :
Write the operation / formula the keywords signify.
The mass of a packet of biscuits is 1.25 kg.
( )
What is the total mass of 3 packets of biscuits ?
Step 3 : Multiply
.
1.25 kg 3
1.25 kg
3
3.75 kg Answer : 3.75 kg
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WAJA MATHS YEAR 4 JPN PERAK
8.
9. tenths
10. hundredths
Exercise 9
Solve the problems.
1 The length of a hockey stick is 68.5 cm. Find the total length of 3 similar
hockey sticks.
2 A bowl can hold 73.4 g of flour. Lina used 6 bowls of flour for baking a cake.
How much flour did Lina use?
78
as n t e or er g ven.
Step 2: Step 3:
RM8000 RM9254
+ RM1254 RM5555
RM9254 RM3699
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WAJA MATHS YEAR 4 JPN PERAK
3 A tank can hold 13.6 litres of oil when it is full.
How much oil can 6 tanks hold?
10. Divide decimal of one decimal place and two decimal places by : a) one-digit number, b) 10,
Example 1
79
4.6 2 =Arrange in
vertical form
Divide digit by digit from
left to right
2 4 . 6
2 . 3
2 4 .64
0 6
6
0
Lets try
this !!!
Place the decimal point.
in line with decimal point of
dividend
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WAJA MATHS YEAR 4 JPN PERAK
Example 2
6 7 9 2
80
4.8 4 =
7.92 6 =
Set the time table of 61 = 6
2 = 12
3 = 18
4 = 245 = 30
6 = 367 = 42
8 = 489 = 54
6 7 9 2
.
. Arrange in vertical form.
Place the decimal pointin line with decimal point
of dividend.
.1. 3 2
- 6
1 9
1 8
1 2
- 1 2
0 0
Divide digit by digit
from left to right.
Regroup if necessary.
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Example 3
Example 4
81
1.32
Answer
23.5 5 =
0.8 10 =
0.8 10 Move decimal point1 place to the left
TIPS
10 has 1 zero means one move
0.08
34.7 10 =
34.7 10Move decimal point
1 place to the left.
Lets try this !!!
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WAJA MATHS YEAR 4 JPN PERAK
Exercise 10
Divide
1 6.2 2 = 2 6.5 5 =
3 12.6 6 = 4 4.64 8 =
82
3.47
6.9 10 =
45.3 10 =
27.5 10 =
Lets try this !!!
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WAJA MATHS YEAR 4 JPN PERAK
5 25.5 10 = 6 13.5 10 =
11. Divide decimals by a whole number with the dividend value of up to two decimal places.
Example 2
5 15 7 0
83
15.7 5 =
Set the time table 51 = 5
2 = 103 = 15
4 = 205 = 25
6 = 307 = 35
8 = 409 = 45
5 15 7
.
. Arrange in vertical form. Place the decimal point
in line with decimal point
of dividend.
.3. 1 4
- 15
0 7
5
2 0
- 2 0
0 0
Divide digit by digit from
left to right.
Regroup if necessary.
Put a zero to the dividendwherever there is a remainder
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WAJA MATHS YEAR 4 JPN PERAK
Exercise 11
Divide.
.
1 10.08 3 = 2 2.28 6 =
3 15.7 5 = 4 18.2 4 =
84
3.14 Answer
18.8 8 =
Lets try
this !!!
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WAJA MATHS YEAR 4 JPN PERAK
5 69.45 3 = 6 496.4 8 =
12. Solve problems involving division of decimal numbers.
19. .120. 0.1
21. 0.05
22. 24.26
23. 42.33
24. 70.39
28. or point seven
29. six point nine
30. eight point eight
31. five point one
32. three point zero seven33. sixty-two point three five
34. fifty point zero five
35. thirteen point two eight
36. seventy-six point eight six
19. 1 decimal place
20. 1 decimal place
21. 2 decimal places
22. 2 decimal places
23. 2 decimal places
24. 1 decimal place
85
EXAMPLE HOW TO SOLVE
EXAMPLE
17.7 kg of rice has been divided between three floodvictims. How many kilograms of rice are provided to
each victim?
Step 1 :
Read and understand question. As you read underline the
keywords.
17.7 kg of rice has been divided between three flood
victims. How many kilograms of rice are provided to eachvictim?
Step 2 :
Write the operation / formula the keywords signify.
17.7 kg of rice has been divided between three flood
victims. How many kilograms of rice is provided to
( )
each victim?
Step 3 : Divide
5.9
3 17.7
15
2 7
2 70 0 Answer : 5.9 kg
Note : + and are on the same scale. So calculate
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WAJA MATHS YEAR 4 JPN PERAK
11.
12. tenths
13. hundredths
Exercise 12
Solve the problems.
1 The total length of 4 equal pieces of ribbon is 20.08 cm.
Find the length of each piece of ribbon.
2 Roslan packed 6.6 kg of rice into four bags equally.
What is the weight, in kg, of rice in each bag?
86
Step 2: Step 3:
RM8000 RM9254
+ RM1254 RM5555
RM9254 RM3699
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3 Raja pours 9.84 of syrup equally into 8 bottles.
What is the volume, in , of a bottle?