beams_unit 2 fractions
TRANSCRIPT
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Unit 1:Negative Numbers
UNIT 2
FRACTIONS
B a s i c E s s e n t i a l
A d d i t i o n a l M a t h e m a t i c s S k i l l s
Curriculum Development Division
Ministry of Education Malaysia
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TABLE OF CONTENTS
Module Overview 1
Part A: Addition and Subtraction of Fractions 2
1.0 Addition and Subtraction of Fractions with the Same Denominator 5
1.1 Addition of Fractions with the Same Denominators 5
1.2 Subtraction of Fractions with The Same Denominators 6
1.3 Addition and Subtraction Involving Whole Numbers and Fractions 7
1.4 Addition or Subtraction Involving Mixed Numbers and Fractions 9
2.0 Addition and Subtraction of Fractions with Different Denominator 10
2.1 Addition and Subtraction of Fractions When the Denominator
of One Fraction is A Multiple of That of the Other Fraction 11
2.2 Addition and Subtraction of Fractions When the Denominators
Are Not Multiple of One Another 13
2.3 Addition or Subtraction of Mixed Numbers with Different
Denominators 16
2.4 Addition or Subtraction of Algebraic Expression with Different
Denominators 17
Part B: Multiplication and Division of Fractions 22
1.0 Multiplication of Fractions 24
1.1 Multiplication of Simple Fractions 28
1.2 Multiplication of Fractions with Common Factors 29
1.3 Multiplication of a Whole Number and a Fraction 29
1.4 Multiplication of Algebraic Fractions 312.0 Division of Fractions 33
2.1 Division of Simple Fractions 36
2.2 Division of Fractions with Common Factors 37
Answers 42
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Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
1Curriculum Development DivisionMinistry of Education Malaysia
PART 1
MODULE OVERVIEW
1. The aim of this module is to reinforce pupils understanding of the conceptof fractions.
2. It serves as a guide for teachers in helping pupils to master the basiccomputation skills (addition, subtraction, multiplication and division)
involving integers and fractions.
3. This module consists of two parts, and each part consists of learningobjectives which can be taught separately. Teachers may use any parts of the
module as and when it is required.
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UNIT 2: Fractions
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PART A:ADDITION AND SUBTRACTION
OF FRACTIONS
LEARNING OBJECTIVES
Upon completion ofPart A, pupils will be able to:
1. perform computations involving combination of two or more operationson integers and fractions;
2. pose and solve problems involving integers and fractions;3. add or subtract two algebraic fractions with the same denominators;4. add or subtract two algebraic fractions with one denominator as a
multiple of the other denominator; and
5. add or subtract two algebraic fractions with denominators:(i) not having any common factor;(ii) having a common factor.
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UNIT 2: Fractions
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TEACHING AND LEARNING STRATEGIES
Pupils have difficulties in adding and subtracting fractions with different
denominators.
Strategy:
Teachers should emphasise that pupils have to find the equivalent form of
the fractions with common denominators by finding the lowest common
multiple (LCM) of the denominators.
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numerator
denominator
Fraction is written in the form of:
b
a
Examples:
3
4,
3
2
Proper Fraction Improper Fraction Mixed Numbers
The numerator is smaller
than the denominator.
Examples:
20
9,
3
2
The numerator is larger
than or equal to the denominator.
Examples:
12
108,
4
15
A whole number and
a fraction combined.
Examples:
65
71 8,2
Rules for Adding or Subtracting Fractions
1. When the denominators are the same, add or subtract only the numerators andkeep the denominator the same in the answer.
2. When the denominators are different, find the equivalent fractions that have thesame denominator.
Note: Emphasise that mixed numbers and whole numbers must be converted to improper
fractions before adding or subtracting fractions.
LESSON NOTES
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UNIT 2: Fractions
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1.0 Addition And Subtraction of Fractions with the Same Denominator
1.1 Addition of Fractions with the Same Denominators
8
5
8
4
8
1i)
2
1
8
4
8
3
8
1ii)
fff
651
iii)
EXAMPLES
Add only the numerators and keep the
denominator same.
Write the fraction in its simplest form.
Add only the numerators and keep the
denominator the same.
Add only the numerators and keep the
denominator the same.
8
1
8
4
8
5
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1.2 Subtraction of Fractions with The Same Denominators
2
1
8
4
8
1
8
5i)
7
4
7
5
7
1ii)
nnn
213iii)
Write the fraction in its simplest form.
Subtract only the numerators and keep
the denominator the same.
Subtract only the numerators and keep
the denominator the same.
Subtract only the numerators and keep
the denominator the same.
8
5
8
1
2
1
8
4
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1.3 Addition and Subtraction Involving Whole Numbers and Fractions
.
8
11Calculatei)
7
29
7
1
7
28
7
14
7
14
5
18
5
2
5
20
5
24
5
33
3
12
3
1
3
12
3
14
y
yy
First, convert the whole number to an improper fraction with thesame denominator as that of the other fraction.
Then, add or subtract only the numerators and keep the denominatorthe same.
18
1
8
11
8
9
+
8
8
+
8
1
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n
n
nn
n
n
52
5252
k
k
k
k
kk
32
323
2
First, convert the whole number to an improper fraction withthe same denominator as that of the other fraction.
Then, add or subtract only the numerators and keep thedenominator the same.
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1.4 Addition or Subtraction Involving Mixed Numbers and Fractions
.8
4
8
11Calculatei)
7
5
7
15
7
5
7
12
= 7
20
= 7
6
2
9
4
9
29
9
4
9
23
= 9
25
= 9
7
2
88
11
88
31
xx
= 8
11 x
First, convert the mixed number to improper fraction. Then, add or subtract only the numerators and keep the
denominator the same.
811
84
8
51
8
13
+
8
9
+
8
4
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2.0 Addition and Subtraction of Fractions with Different Denominators
.2
1
8
1Calculatei)
To make the denominators the same, multiply both the numerator and the denominator of
the second fraction by 4:
Now, the question can be visualized like this:
?
The denominators are not the same.
See how the slices are different insizes? Before we can add the
fractions, we need to make them the
same, because we can't add them
to ether like this!
8
1
8
4
+
8
5
8
4
2
1
4
4
Now, the denominators
are the same. Therefore,we can add the fractions
together!
8
1
2
1
+
?
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Hint: Before adding or subtracting fractions with different denominators, we must
convert each fraction to an equivalent fraction with the same denominator.2.1 Addition and Subtraction of Fractions When the Denominator of One Fraction is
A Multiple of That of the Other Fraction
Multiply both the numerator and the denominator with an integer that makes the
denominators the same.
(i)6
5
3
1
6
5
6
2
6
7
=6
11
(ii)4
3
12
7
12
9
12
7
12
2
6
1
Change the first fraction to an equivalent
fraction with denominator 6.
(Multiply both the numerator and thedenominator of the first fraction by 2):
6
2
3
1 2
2
Add only the numerators and keep the
denominator the same.
Change the second fraction to an equivalentfraction with denominator 12.
(Multiply both the numerator and the
denominator of the second fraction by 3):
12
9
4
3 3
3
Subtract only the numerators and keep the
denominator the same.
Write the fraction in its simplest form.
Convert the fraction to a mixed number.
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(iii) vv 5
91
vv 5
9
5
5
v5
14
Change the first fraction to an equivalent
fraction with denominator 5v.(Multiply both the numerator and thedenominator of the first fraction by 5):
vv 5
51 5
5
Add only the numerators and keep the
denominator the same.
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UNIT 2: Fractions
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2.2 Addition and Subtraction of Fractions When the Denominators Are Not Multiple of
One Another
Method I
4
3
6
1
(i) Find the Least Common Multiple (LCM)
of the denominators.
2) 4 , 62) 2 , 3
3) 1 , 3- , 1
LCM = 2 2 3 = 12
The LCM of 4 and 6 is 12.
(ii) Change each fraction to an equivalent
fraction using the LCM as thedenominator.
( Multiply both the numerator and thedenominator of each fraction by a whole
number that will make their
denominators the same as the LCM
value).
=
4
3
6
1
=12
9
12
2
=12
11
Method II
4
3
6
1
(i) Multiply the numerator and thedenominator of the first fraction withthe denominator of the second fraction
and vice versa.
=4
3
6
1
=24
18
24
4
=24
22
=12
11
Write the fraction in its
simplest form.
This method is preferred but youmust remember to give the
answer in its simplest form.3
3
22
44 6
6
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Multiply the first fraction with the second denominator
and
multiply the second fraction with the first denominator.
1.5
1
3
2
=5
5
3
2
+
3
3
5
1
15
3
15
10
=15
13
2.8
3
6
5
=
8
8
6
5
6
6
8
3
=48
18
48
40
=48
22
=24
11
Write the fraction in its simplest form.
EXAMPLES
Multiply the first fraction by the
denominator of the second fraction andmultiply the second fraction by the
denominator of the first fraction.
Multiply the first fraction by the
denominator of the second fraction and
multiply the second fraction by thedenominator of the first fraction.
Add only the numerators and keep the
denominator the same.
Subtract only the numerators and keep
the denominator the same.
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3.7
1
3
2g
=3
3
7
7
7
1
3
2
g
=21
3
21
14
g
=21
314 g
4.53
2 hg
3
3
55
5
3
2
hg
15
3
15
10 hg
15
310 hg
5.dc
46
=
c
c
d
d
dc
46
cd
c
cd
d 46
=cd
cd 46
Multiply the first fraction by thedenominator of the second fraction and
multiply the second fraction by the
denominator of the first fraction.
Write as a single fraction.
Write as a single fraction.
Write as a single fraction.
Multiply the first fraction by the
denominator of the second fraction and
multiply the second fraction by thedenominator of the first fraction.
Multiply the first fraction by thedenominator of the second fraction and
multiply the second fraction by thedenominator of the first fraction.
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Convert the mixed numbers to improper fractions.
Convert the mixed numbers to improper fractions.
2.3 Addition or Subtraction of Mixed Numbers with Different Denominators
1.4
32
2
12
=4
11
2
5
=4
11
2
5
2
2
=4
11
4
10
=4
21
4
15
2.4
31
6
53
=4
7
6
23
=6
6
4
4
4
7
6
23
=24
42
24
92
=24
50
=12
25
=12
12
Change the first fraction to an equivalent fraction
with denominator 4.(Multiply both the numerator and the denominator
of the first fraction by 2)
The denominators are not multiples of one another:
Multiply the first fraction by the denominatorof the second fraction.
Multiply the second fraction by thedenominator of the first fraction.
Convert the mixed numbers to improper fractions.
Convert the mixed numbers to improper fractions.
Add only the numerators and keep the
denominator the same.
Change the fraction back to a mixed number.
Add only the numerators and keep the
denominator the same.
Change the fraction back to a mixed number.
Write the fraction in its simplest form.
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The denominators are not multiples of one anotherMultiply the first fraction with the second denominator
Multiply the second fraction with the first denominator
The denominators are not multiples of one anotherMultiply the first fraction with the second denominatorMultiply the second fraction with the first denominator
2.4Addition or Subtraction of Algebraic Expression with Different Denominators
1.22
m
m
m
=)2(
)2(
2
2
22
m
mm
m
m
=
22
2
22
2
m
mm
m
m
=)2(2
)2(2
m
mmm
=)2(2
222
m
mmm
=)2(2
2
m
m
2.y
y
y
y 1
1
=
)1(
)1(1
1
y
y
y
y
y
y
y
y
=
)1(
)1)(1(2
yy
yyy
=)1(
)1(22
yy
yy
=)1(
122
yy
yy
=)1(
1
yy
Remember to usebrackets
Write the above fractions as a singlefraction.
The denominators are not multiples of one another:
Multiply the first fraction by the denominatorof the second fraction.
Multiply the second fraction by thedenominator of the first fraction.
Expand:
m (m2) = m22m
Expand:
(y1) (y + 1) =y2 +yy12
=y21
Expand:
(y21) =y2 + 1
Write the fractions as a singlefraction.
The denominators are not multiples of one another:
Multiply the first fraction by the denominatorof the second fraction.
Multiply the second fraction by thedenominator of the first fraction.
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The denominators are not multiples of one anotherMultiply the first fraction with the second denominator
Multiply the second fraction with the first denominator
3.
24
5
8
3
n
n
n
=n
n
n
n
n
n
n 8
8
24
4
4
5
8
3
2
2
=)4(8
)5(8
)4(8
1222
2
nn
nn
nn
n
= )4(8
)5(812
2
2
nn
nnn
=)4(8
84012
2
22
nn
nnn
=)4(8
404
2
2
nn
nn
=
)8(4
)10(4
2
nn
nn
=2
8
10
n
n
Factorise and simplify the fraction by canceling
out the common factors.
Expand:
8n (5 + n) =40n8n2
Subtract the like terms.
Write as a singlefraction.
The denominators are not multiples of one another:
Multiply the first fraction by the denominatorof the second fraction.
Multiply the second fraction by thedenominator of the first fraction.
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UNIT 2: Fractions
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Calculate each of the following.
1. 7
1
7
2
2.
12
5
12
11
3. 14
1
7
2
4.
12
5
3
2
5. 5
4
7
2
6. 7
5
2
1
7. 313
22
8. 9
72
5
24
9. ss
12
10.
ww
511
TEST YOURSELF A
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11. aa 2
12
12. ff 3
52
13. ba
42
14. qp
51
15. nmnm5
3
7
2
5
2
7
5
16.
)2(2
1p
p
17. 5
3
2
32 yxyx
18. xx
x 5
2
412
19.
x
x
x
x 1
1 20.
2
4
2 x
x
x
x
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21.
4
84
2
36 yxyx
22.
2
9
4
3
2
n
n
n
23.
r
rr
15
25
5
2
24.
p
p
p
p
2
232
25.
n
n
n
n
10
34
5
322
26.
n
n
mn
nm 33
27.
mn
nm
m
m
5
5
28.
mn
mn
m
m
3
3
29.
24
5
8
3
n
n
n 30.
m
p
m
p 1
3
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PART B:
MULTIPLICATION AND DIVISION
OF FRACTIONS
LEARNING OBJECTIVES
Upon completion ofPart B, pupils will be able to:
1. multiply:
(i) a whole number by a fraction or mixed number;
(ii) a fraction by a whole number (include mixed numbers); and
(iii) a fraction by a fraction.
2. divide:
(i) a fraction by a whole number;
(ii) a fraction by a fraction;
(iii) a whole number by a fraction; and
(iv) a mixed number by a mixed number.
3. solve problems involving combined operations of addition, subtraction,
multiplication and division of fractions, including the use of brackets.
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TEACHING AND LEARNING STRATEGIES
Pupils face problems in multiplication and division of fractions.
Strategy:
Teacher should emphasise on how to divide fractions correctly. Teacher should
also highlight the changes in the positive (+) and negative () signs as follows:
Multiplication Division
(+) (+) = + (+) (+) = +
(+) () = (+) () =
() (+) = () (+) =
() () = + () () = +
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1.0Multiplication of Fractions
Recall that multiplication is just repeated addition.
Consider the following:
32
First,lets assume this box as 1 whole unit.
Therefore, the above multiplication 32 can be represented visually as follows:
This means that 3 units are being repeated twice, or mathematically can be written as:
6
3332
Now, lets calculate 2 x 2. This multiplication can be represented visually as:
This means that 2 units are being repeated twice, or mathematically can be written as:
4
2222
LESSON NOTES
3 + 3 = 6
2 + 2 = 4
2 groups of 3 units
2 groups of 2 units
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Now, lets calculate 2 x 1. This multiplication can be represented visually as:
This means that 1 unit is being repeated twice, or mathematically can be written as:
21112
It looks simple when we multiply a whole number by a whole number. What if we
have a multiplication ofa fraction by a whole number? Can we represent it visually?
Lets consider .2
12
Since represents 1 whole unit, therefore2
1unit can be represented by the
following shaded area:
Then, we can represent visually the multiplication of2
12 as follows:
This means that2
1unit is being repeated twice, or mathematically can be written as:
1
2
2
2
1
2
1
2
12
1 + 1 = 2
2
1+
2
1= 1
2
2
2 groups of 1 unit
2 groups of2
1unit
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Lets consider again .22
1 What does it mean? It means
2
1out of 2 units and the
visualization will be like this:
Notice that the multiplications2
12 and 2
2
1 will give the same answer, that is, 1.
How about ?2
3
1
Since represents 1 whole unit, therefore3
1unit can be represented by the
following shaded area:
Then, we can represent visually the multiplication 23
1 as follows:
This means that3
1unit is being repeated twice, or mathematically can be written as:
3
2
3
1
3
12
3
1
3
1+
3
1=
3
2
The shaded area is 3
1unit.
2
1out of 2 units 12
2
1
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Lets consider 23
1 . What does it mean? It means
3
1out of 2 units and the visualization
will be like this:
Notice that the multiplications3
12 and 2
3
1 will give the same answer, that is,
3
2.
Consider now themultiplication of a fraction by a fraction, like this:
21
31
This means 3
1out of
2
1units and the visualization will be like this:
Consider now thismultiplication:
2
1
3
2
This means
3
2out of
2
1units and the visualization will be like this:
2
1unit
3
1out of 2 units
3
22
3
1
3
1out of
2
1units
6
1
2
1
3
1
2
1unit
3
2out of
2
1units
6
2
2
1
3
2
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What do you notice so far?
The answer to the above multiplication of a fraction by a fraction can be obtained by
just multiplying both the numerator together and the denominator together:
6
1
2
1
3
1
9
2
3
1
3
2
So, what do you think the answer for3
1
4
1 ? Do you get
12
1as the answer?
The steps to multiply a fraction by a fraction can therefore be summarized as follows:
1.1 Multiplication ofSimple Fractions
Examples:
a)35
6
7
3
5
2 b)
35
6
5
3
7
2
c)35
12
5
2
7
6 d)
35
12
5
2
7
6
Steps to Multiply Fractions:
1) Multiply the numerators together andmultiply the denominators together.
2) Simplify the fraction (if needed).
Remember!!!
(+) (+) = +
(+) () =
() (+) =
() () = +
Multiply the two numerators together and the two denominators together.
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Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
29Curriculum Development DivisionMinistry of Education Malaysia
1.2 Multiplication of Fractions with Common Factors
6
5
7
12 or
6
5
7
12
1.3 Multiplication of a Whole Number and a Fraction
6
152
=
6
31
1
2
=
6
31
1
2
=3
31
=3
110
Second Method:
(i) Simplify the fraction by cancelingout the common factors.
6
5
7
12
(i) Then, multiply the twonumerators together and the twodenominators together, andconvert to a mixed number, if
needed.
6
5
7
12
7
31
7
10
2
1
Convert the mixed number to improper
fraction.
Simplify by canceling out the common
factors.
Remember
2 =1
2
First Method:
(ii)Multiply the two numeratorstogether and the twodenominators together:
6
5
7
12 =
42
60
(ii) Then, simplify.
7
31
7
10
42
60
10
7
3Multiply the two numerators together and
the two denominators together.
Remember: (+) () = ()
Change the fraction back to a mixed number.
1
1
2
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8/9/2019 BEAMS_Unit 2 Fractions
32/45
Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
30Curriculum Development DivisionMinistry of Education Malaysia
1. Find10
15
12
5
Solution:10
15
12
5
=8
5
2. Find5
2
6
21
Solution :5
2
6
21
=5
2
6
21
5
7
=5
21
Simplify by canceling out the common
factors.
Note that3
21can be further simplified.
Simplify further by canceling out the
common factors.
3
1
Simplify by canceling out the common factors.
EXAMPLES
Multiply the two numerators together and the
two denominators together.
Remember: (+) () = ()
Multiply the two numerators together and
the two denominators together.
Remember: (+) () = ()
3
1
1
7
Change the fraction back to a mixed
number.
2
1
4
5
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8/9/2019 BEAMS_Unit 2 Fractions
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Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
31Curriculum Development DivisionMinistry of Education Malaysia
1.4 Multiplication of Algebraic Fractions
1. Simplify 4
52 x
x
Solution :4
52 x
x
=2
5
=212
2. Simplify
m
n
n4
9
2
Solution:
mn
n4
9
2
=
1
4
2
9
2
mn
n
n
=1
)2(
2
9 mn
= nm22
9
1 2
1 1Simplify the fraction by canceling out the xs.
Multiply the two numerators together and
the two denominators together.
Simplify the fraction by canceling the
common factor and the n.
Multiply the two numerators together
and the two denominators together.
Write the fraction in its simplest form.
Change the fraction back to a mixednumber.
2
1
1
1
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8/9/2019 BEAMS_Unit 2 Fractions
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Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
32Curriculum Development DivisionMinistry of Education Malaysia
1. Calculate 27
25
5
92. Calculate
20
14
7
3
12
45
3. Calculate
4
112 4. Calculate
5
14
3
1
5. Simplify
k
m3 6. Simplify )5(
2m
n
7. Simplify
14
3
6
1
1
x
8. Simplify )32(2 dan
9. Simplify
yx10
95
3
2 10. Simplify
x
x 120
4
TEST YOURSELF B1
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8/9/2019 BEAMS_Unit 2 Fractions
35/45
Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
33Curriculum Development DivisionMinistry of Education Malaysia
2.0 Division of Fractions
Consider the following:
36
First,lets assume this circle as 1 whole unit.
Therefore, the above division can be represented visually as follows:
This means that 6 units are being divided into a group of 3 units, or mathematically
can be written as:
236
The above division can also be interpreted as how many 3s can fit into 6. The answer is
2 groups of 3 units can fit into 6 units.
Consider now a division of a fraction by a fraction like this:
.8
1
2
1
LESSON NOTES
How many8
1is in
6 units are being divided into a group of 3
units:
236
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8/9/2019 BEAMS_Unit 2 Fractions
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Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
34Curriculum Development DivisionMinistry of Education Malaysia
This means How many is in ?
8
1
2
1
The answer is 4:
Consider now this division:
.4
1
4
3
This means How many is in ?
4
1
4
3
The answer is 3:But, how do you
calculate the answer?
How many4
1is in ?
4
3
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8/9/2019 BEAMS_Unit 2 Fractions
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Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
35Curriculum Development DivisionMinistry of Education Malaysia
Consider again .236
Actually, the above division can be written as follows:
3
16
3
636
Notice that we can write the division in the multiplication form. But here, we have to
change the second number to its reciprocal.
Therefore, if we have a division of fraction by a fraction, we can do the same, that is,
we have to change the second fraction to its reciprocal and then multiply the
fractions.
Therefore, in our earlier examples, we can have:
4
2
8
1
8
2
1
8
1
2
1(i)
The reciprocal of a
fraction is found by
inverting the
fraction.
Change the second fraction to its
reciprocal and change the sign to .
The reciprocal
of8
1is .
1
8
These operations are the same!
The reciprocal
of3 is .3
1
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Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
36Curriculum Development DivisionMinistry of Education Malaysia
3
1
4
4
3
4
1
4
3(ii)
The steps to divide fractions can therefore be summarized as follows:
2.1 Division of Simple Fractions
Example:
7
3
5
2
=3
7
5
2
=15
14
Change the second fraction to its reciprocal
and change the sign to .
Multiply the two numerators together and
the two denominators together.
Steps to Divide Fractions:
1. Change the second fraction to itsreciprocal and change the sign to .
2. Multiply the numerators together andmultiply the denominators together.
3. Simplify the fraction (if needed).
Tips:
(+) (+) = +
(+) () =
() (+) =
() () = +
Change the second fraction to its
reciprocal and change the sign to .
The reciprocal
of4
1is .
1
4
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8/9/2019 BEAMS_Unit 2 Fractions
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Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
37Curriculum Development DivisionMinistry of Education Malaysia
2.2 Division of Fractions With Common Factors
Examples:
9
2
21
10
=2
9
21
10
=2
9
21
10
=7
15
=7
12
7
6
5
3
6
7
5
3
10
7
7
65
3
1
5 3
7
1
2
Express the fraction in division form.
Change the second fraction to its reciprocal and
change the sign to .
Simplify by canceling out the common factors.
Change the fraction back to a mixed number.
Change the second fraction to its reciprocal
and change the sign to .
Then, simplify by canceling out the common
factors.
Multiply the two numerators together and the
two denominators together.
Remember: (+) () = ()
Multiply the two numerators together and thetwo denominators together.
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8/9/2019 BEAMS_Unit 2 Fractions
40/45
Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
38Curriculum Development DivisionMinistry of Education Malaysia
1. Find6
25
12
35
Solution :6
25
12
35
=25
6
12
35
=
10
7
2. Simplify 4
52 x
x
Solution : xx 5
42
= 2
5
8
x
3. Simplify2
x
y
Solution :
2x
y
2
1x
y
x
y
2
5
7
Change the second fraction to its reciprocal
and change the sign to .Then, simplify by canceling out the common
factors.
Method I
EXAMPLES
Change the second fraction to its reciprocal
and change the sign to .
Multiply the two numerators together and the twodenominators together.
Express the fraction in division form.
Change the second fraction to its reciprocal
and change to .
Multiply the two numerators together and the two
denominators together.
Remember: (+) () = ()
Multiply the two numerators together and the
two denominators together.
2
1
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8/9/2019 BEAMS_Unit 2 Fractions
41/45
Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
39Curriculum Development DivisionMinistry of Education Malaysia
Multiply the numerator and the denominator of
the given fraction with x
2
x
y
=
2x
y
x
x
=x
xx
y
2
=
x
y
2
4. Simplify5
)1( 1r
Solution:
5
)1( 1r
=
5
)1
1(r
r
r
=
r
r
5
1
The given fraction.
ris the denominator ofr
1.
Multiply the given fraction withr
r.
Note that:
1)1
1( rrr
Method II
The numerator is also
a fraction with
denominatorx
Multiply the numerator and the denominator of the
given fraction byx.
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8/9/2019 BEAMS_Unit 2 Fractions
42/45
Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
40Curriculum Development DivisionMinistry of Education Malaysia
1. Calculate2
21
7
3 2. Calculate165
87
95
3. Simplify3
48 y
y
4. Simplify
k
2
16
5. Simplify
3
5
2
x 6. Simplify
n
m
n
m
3
242
7. Simplify8
1
4
y
8. Simplify
x
x
11
TEST YOURSELF B2
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8/9/2019 BEAMS_Unit 2 Fractions
43/45
Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
41Curriculum Development DivisionMinistry of Education Malaysia
9. Calculate5
)1(341
10. Simplifyy
x15
11. Simplify
3
2
9
41 x
12. Simplify
15
1
1
p
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8/9/2019 BEAMS_Unit 2 Fractions
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Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
42Curriculum Development DivisionMinistry of Education Malaysia
TEST YOURSELF A:
1.7
3
2.
2
1
3.
14
5
4.4
1
5.
35
38or
35
31
6.
14
3
7.13
67or
13
25
8.45
73or
45
281
9.s
3
10.w
6
11.
a2
5
12.
f3
1
13.ab
ab 42
14.
pq
pq 5
15. nm
16.2
33 p
17.10
1716 yx
18.x
x 12
19.)1(
1
xx
20. 2 21.2
8 yx
22.2
9
47
n
n
23.
r
r
3
12
24.2
2
2
6
p
p
25.2
2
10
647
n
nn
26.m
m1
27.
n
n
5
5
28.n
n
3
3
29.
28
10
n
n
30.
m
p
3
34
ANSWERS
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8/9/2019 BEAMS_Unit 2 Fractions
45/45
Basic Essential Additional Mathematics Skills (BEAMS) Module
UNIT 2: Fractions
TEST YOURSELF B1:
1.3
21
3
5or 2.
8
11
8
9 or 3.
2
15
2
11or
4.5
21
5
7 or 5.
k
m36.
2
5mn
7.4
x8. ndna
2
3 9. yx
5
3
3
10
10.
4
15 x
TEST YOURSELF B2:
1.49
22.
9
51
9
14 or 3.
2
6
y
4. 8k5.
x5
66.
m
6
7.)1(2
1
y 8.
1
2
x
x
9.20
9
10.xy
x 15 11.
6
13x 12.
p4
5