12. [Decimals / Fractions / Percentages]
Skill 12.1
Illustrating fractions and percentages.
To recognise a shaded fraction of a shape:
• Count the total number of equal parts in
which the shape is divided.
• Use this number as the denominator of the
fraction.
• Count the number of shaded parts.
• Use this number as the numerator of the
fraction.
• Simplify the resulting fraction.
(see skill 9.1, page 39)
is shaded?
a)
×5
×5
= 30 out of 100 parts
= 30%
What fraction of the shape is shaded?
=
1 out of 4 parts
..............................................................................................
c)
To recognise a shaded percentage of a
shape:
• Count the shaded parts.
• Relate the amount shaded to out of 100,
by dividing the number of total parts into
100.
Hints: A percentage is a fraction out of 100.
Compare to common fractions, like one half
equals 50%, one quarter equals 25% or one
tenth equals 10%.
A. 6 out of 20 parts =
Q. What percentage of the shape
=
..............................................................................................
d) What fraction of the shape is shaded?
=
e)
6 out of 20 parts are shaded.
There are 5 lots of 20 in 100
so multiply 6 × 5 to get the
percentage shaded.
b) What fraction of the shape is shaded?
1
4
What fraction of the shape is shaded?
MM4.2 1 1 2 2 3 3 4 4
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=
...............................................................................................
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What percentage of the shape is shaded? f)
What percentage of the shape is shaded?
=
=
.........................................................................................
.........................................................................................
g) What percentage of the shape is shaded?
=
.........................................................................................
page 75
h) What percentage of the shape is shaded?
=
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© Maths Mate 4.2/5.1 Skill Builder 12
continues on page 77
Skill 12.2
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Simplifying fractions (1).
Highest Common Factor (HCF) of two numbers
• Write all the factors of each number (the factors must divide exactly into the number).
• Find the largest number that appears on both lists.
Hint: The Highest Common Factor is the largest number that divides evenly in both numbers.
Examples:
One number divides evenly
into the other number
Identical numbers
5
5
1
5
1
5
GCF of 5 and 5
4
12
1
2
4
1
2
3
4
6
12
Numbers have other
common factors
HCF of 4 and 12
Hint: 4 is the HCF of 4 and
12 because 4 is the
largest number that
divides into 4 and 12.
Hint: 5 is the HCF of 5 and
5 because 5 is the
largest number that
divides into 5 and 5.
6
10
1
2
3
6
1
2
5
10
HCF of 6 and 10
Hint: 2 is the HCF of 6 and
10 because 2 is the
largest number that
divides into 6 and 10.
• Divide both the numerator and the denominator by their Highest Common Factor (HCF).
OR
• Divide both the numerator and the denominator by any common factor.
• Divide again by another common factor, until the common factor of the numerator and the
denominator is 1.
Hints: The fraction is in simplest form when it cannot be simplified.
If the numbers are both even then you can start with dividing by 2.
Q. Simplify
20
30
A.
=
=
20
=
30
20
30
2
3
HCF of 20 and 30 is 10
÷ 10
OR A.
=
Divide by 10
÷ 10
=
20
30
÷2
10
15
÷5
2
3
÷2
=
Divide by 2
Divide by 5
÷5
HCF of 4 and 10 is 2
4
a) Simplify
10
b) Simplify
4 ÷2
=
=
10 ÷ 2
..............................................
d) Simplify
=
3
9
=
=
Simplify
c)
=
Simplify
=
2
8
=
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=
..............................................
Simplify
f)
..............................................
4
6
=
..............................................
e)
..............................................
page 76
2
5
3
6
=
2
6
=
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© Maths Mate 4.2/5.1 Skill Builder 12
continued from page 76
Skill 12.2
g) Simplify
9
18
=
h) Simplify
=
Simplify
8
12
=
=
=
=
=
=
9
24
=
=
=
..............................................
Simplify
v)
9
15
=
=
Simplify
=
20
25
=
page 77
Simplify
=
8
28
=
..............................................
Simplify
x)
=
=
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25
35
=
=
..............................................
zz) Simplify
..............................................
24
30
=
..............................................
z)
..............................................
u) Simplify
9
81
=
=
..............................................
=
w) Simplify
14
21
=
..............................................
..............................................
y)
Simplify
r)
8
20
=
..............................................
=
Simplify
10
30
=
..............................................
t)
=
..............................................
o) Simplify
8
16
15
20
=
=
q) Simplify
=
Simplify
Simplify
..............................................
..............................................
s)
=
=
=
..............................................
l)
4
40
12
15
=
..............................................
n) Simplify
5
25
5
15
=
..............................................
p) Simplify
=
Simplify
k)
6
12
Simplify
i)
..............................................
..............................................
m) Simplify
3
30
=
..............................................
j)
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Simplifying fractions (2).
=
12
20
=
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© Maths Mate 4.2/5.1 Skill Builder 12
Skill 12.3
•
•
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Finding equivalent fractions.
Check if you need to multiply or divide the numerator or denominator of the first fraction to
reach the numerator or denominator of the second fraction.
Do the same operation to the top or the bottom of the fraction.
Example:
×3
?
12
12
4
4
So and
are equivalent fractions.
=
⇒ 4 =
15
5 × 3 15
5
5 15
×3
Q. Complete the equivalent
fractions:
3
18
=
=
5
90
a) Complete the equivalent
fractions:
×6
A. 3 18
=
5 ?
3 × 6 18
=
5 × 6 30
3 × 18 54
=
⇒
5 × 18 90
⇒
and 3 = ?
5 90
30
× 18
b) Complete the equivalent
fractions:
c) Complete the equivalent
fractions:
3
27
=
4
35
5
=
42
6
? 5
= ⇒ ? ÷ 7 = 5 ⇒ ? = 35
42 6
....................................................................
54
3
18
⇒ =
=
5
90
2
=
5
35
3 × 9 27
3 27
=
⇒
=
4 × 9 36
4 ?
....................................................................
⇒
....................................................................
÷7
d) Complete the equivalent
fractions:
4
=
e) Complete the equivalent
28
49
⇒
....................................................................
g) Complete the equivalent
h) Complete the equivalent
2
40
=
=
3
15
3
12
=
=
8
96
fractions:
⇒
and
⇒
....................................................................
page 78
48 12
=
60
⇒
....................................................................
....................................................................
Complete the equivalent
fractions:
9
=
10
60
⇒
fractions:
f)
fractions:
...................................................................
i)
Complete the equivalent
fractions:
3
⇒
...................................................................
and
⇒
...................................................................
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=
6
=
8
64
⇒
....................................................................
and
⇒
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© Maths Mate 4.2/5.1 Skill Builder 12
Skill 12.4
•
•
Multiply the decimal number by 100, by moving the decimal point two places to the right.
Add the percentage sign.
Hint: Zeros can be added at the end of any decimal number: 0.4 = 0.4000
A. 0.07 = 0.07 × 100%
= 7%
Q. Write 0.07 as a percentage.
a)
Write 0.4 as a percentage.
0.4
= 0.40 × 100%
=
.................................................................................
Write 0.1 as a percentage.
40%
=
.................................................................................
d) Write 0.9 as a percentage.
=
=
.................................................................................
e)
Write 0.7 as a percentage.
.................................................................................
f)
=
g) Write 0.55 as a percentage.
.................................................................................
h) Write 0.48 as a percentage.
=
=
.................................................................................
Write 0.29 as a percentage.
.................................................................................
j)
=
Write 0.04 as a percentage.
.................................................................................
l)
=
.................................................................................
n) Write 0.38 as a percentage.
=
=
.................................................................................
o) Write 0.4 as a percentage.
.................................................................................
p) Write 0.25 as a percentage.
=
=
.................................................................................
q) Write 0.125 as a percentage.
.................................................................................
r)
=
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page 79
Write 0.05 as a percentage.
=
.................................................................................
m) Write 0.02 as a percentage.
Write 0.35 as a percentage.
=
.................................................................................
k)
Write 0.12 as a percentage.
=
.................................................................................
i)
2 zeros, 2 places to
the right
b) Write 0.2 as a percentage.
Add a zero
c)
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Writing a decimal number as a percentage.
Write 0.345 as a percentage.
=
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© Maths Mate 4.2/5.1 Skill Builder 12
Skill 12.5
•
•
Write the percentage as a fraction out of 100.
Divide the numerator of the fraction by 100, by moving the decimal point two places to the
left.
Hints: Fractions are divisions.
There is a decimal point and zeros which are not written, at the end of any whole number:
27 = 27.00
Zeros can be used as place holders before any whole number: 27 = 0027.00
8.6
100
= 8.6 ÷ 100
= 008.6 ÷ 100
= 0.086
A. 8.6% =
Q. Change 8.6% to a decimal.
a)
Change 5% to a decimal.
5% = 5 = 005.0 ÷ 100
100
2 zeros, 2 places to
the left
b) Change 2% to a decimal.
=
.................................................................................
c)
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Writing a percentage as a decimal number.
2% =
0.05
Change 88% to a decimal.
=
.................................................................................
d) Change 42% to a decimal.
=
=
.................................................................................
e)
.................................................................................
Change 60% to a decimal.
f)
Change 40% to a decimal.
=
=
.................................................................................
.................................................................................
g) Change 0.5% to a decimal.
h) Change 1.8% to a decimal.
=
=
.................................................................................
i)
.................................................................................
In Mali 72% of people earn less than $1
each day. Write this percentage as a
decimal.
j)
In Oct 2010 the unemployment figure
for Australia was 5.1%. Write this
percentage as a decimal.
=
k)
=
.................................................................................
.................................................................................
l)
The percentage of Americans between
12 and 17 who play video games is 97%.
Write this percentage as a decimal.
The Sun accounts for 99% of the mass
of the solar system. Write this
percentage as a decimal.
=
=
.................................................................................
.................................................................................
m) China has approximately 20% of the
world’s population. Write this
percentage as a decimal.
n) On average Australians spend 3.8% of
their day on facebook. Write this
percentage as a decimal.
=
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page 80
=
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© Maths Mate 4.2/5.1 Skill Builder 12
Skill 12.6
•
tenths
hundredths
0
0
4
numerator
4
4 in hundredths place,
denominator = 100
100
Write the fraction in simplest form. This means to divide both the numerator and the
denominator by the same number.
Hint: For the denominator, write 1 followed by a zero for each digit after the decimal point.
4
Example: 0.04 =
100
= 4 hundredths =
Q. Write 0.6 as a fraction in simplest form.
A. 0.6 =
=
=
a)
Write 0.9 as a fraction.
9
Write 0.3 as a fraction.
÷2
6
10 ÷ 2
1 zero for 1
decimal place
Simplify: ÷ 2
3
5
d) Write 0.1 as a fraction.
=
.....................................................................................
.....................................................................................
Write 0.06 as a fraction in simplest form. f)
Write 0.02 as a fraction in simplest form.
=
=
......................................................................................
......................................................................................
g) Write 0.5 as a fraction in simplest form.
i)
Write 6 as the
numerator
0.11
= eleven hundredths
=
.....................................................................................
=
e)
6
10
b) Write 0.11 as a fraction.
0.9
= nine tenths
= 10
.....................................................................................
c)
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Write the decimal number as the numerator of the fraction.
Ignore any zeros at the start the number.
Use the place value of the last digit of the decimal number to determine the size of the
denominator.
Write the 4 as the
Example:
units
•
•
•
Writing a decimal number as a fraction in simplest form.
h) Write 0.28 as a fraction in simplest form.
=
=
......................................................................................
......................................................................................
Write 0.15 as a fraction in simplest form. j)
Write 0.8 as a fraction in simplest form.
=
=
......................................................................................
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page 81
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© Maths Mate 4.2/5.1 Skill Builder 12
Skill 12.7
When the denominator is a power of 10:
• Divide the numerator by the power of 10 by
moving the decimal point to the left.
15
Example:
= 15 ÷ 100
100
2 zeros, 2 places
= 015.0 ÷ 100
to the left
= 0.15
Hints: Fractions are just divisions.
There is a decimal point and zeros which
are not written, at the end of any whole
number:
27 = 27.00
Zeros can be used as place holders before
any whole number: 27 = 0027.00
The number of zeros in the denominator
shows the number of digits
27
after the decimal point.
= 0.27
100
Q. Change
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Writing a fraction as a terminating decimal.
3
to a decimal.
5
A.
3 3 × 20
=
5 5 × 20
When the denominator is not a power
of 10:
EITHER
• Multiply both the numerator and
denominator by the same number to
make the denominator a power of 10.
(e.g. 10, 100 or 1000).
× 25
75
Example: 3 = 3
= 0.75
=
4 4 × 25 100
power of 10
OR
• Divide the numerator by the
denominator.
Example: 3 = 3 ÷ 4 = 3.00 ÷ 4 = 0.75
4
0. 7 5
3 2
4 3. 0 0
OR
A.
Make denominator
60
a power of 10
100
= 60 ÷ 100
2 places
= 060.0 ÷ 100 2 zeros,
to the left
= 0.60 = 0.6
=
3
to a decimal.
10
30
=
100
a) Change
3 × 10
10 × 10
.....................................................................
= ..............................................
030.0 ÷ 100 =
d) Change
0.3
1
to a decimal.
2
.....................................................................
= ..............................................
=
g) In 2008 a quarter of the
Australian wheat exports
went to Indonesia. Write
this fraction as a decimal.
.....................................................................
= ..............................................
=
page 82
b) Change
7
to a decimal.
20
= ..............................................
=
f)
Change 2
3
to a decimal.
4
.....................................................................
.....................................................................
= ..............................................
=
= ..............................................
=
h) Approximately 9 out 10
9
to a decimal.
25
.....................................................................
= ..............................................
=
2
to a decimal.
5
0. 6
3
5 3. 0
c) Change
.....................................................................
e) Change 1
3
=3÷5
5
= 3.0 ÷ 5
= 0.6
Nigerians attend church
regularly. Write this
fraction as a decimal.
People have the smelling
ability of one-twentieth
of that of a dog. Write
this fraction as a decimal.
.....................................................................
.....................................................................
= ..............................................
=
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i)
= ..............................................
=
© Maths Mate 4.2/5.1 Skill Builder 12
Skill 12.8
•
•
Write the percentage as a fraction with the denominator of 100.
Simplify the fraction by dividing both the numerator and the denominator by the same
number.
Hints: Percent means “per hundred” or “out of a hundred”.
A percentage is another way of writing a fraction out of one hundred.
Example: 25% is said “25 percent” and means 25 out of 100.
Q. USA accounts for 24% of the European
Union exports. Write this percentage as
a fraction in simplest form.
a)
Write 47% as a fraction.
......................................................................................
=
24 ÷ 4
100 ÷ 4
Simplify: ÷ 4
6
25
47
100
=
......................................................................................
Write 15% as a fraction in simplest form. d) Write 30% as a fraction in simplest form.
15% =
÷5
15
100 ÷ 5
Simplify: ÷ 5
=
......................................................................................
e)
A. 24% =
b) Write 9% as a fraction.
=
47%
c)
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Writing a percentage as a fraction in simplest form.
3
20
Write 4% as a fraction in simplest form.
=
......................................................................................
f)
Write 6% as a fraction in simplest form.
=
=
......................................................................................
......................................................................................
g) The common metal for medals is 84%
copper. Write this percentage as a
fraction in simplest form.
h) About 67 percent of of all New Zealand
males aged between 18 and 45 served in
WWII. Write this percentage as a
fraction in simplest form.
=
=
......................................................................................
......................................................................................
i)
India is home to 40% of the world’s
poor. Write this percentage as a
fraction in simplest form.
j)
=
In Belgium, 55% of government
ministers are female. Write this
percentage as a fraction in simplest
form.
=
......................................................................................
......................................................................................
k)
The average person’s left hand does
56% of the typing. Write this
percentage as a fraction in simplest
form.
l)
The pupil of the eye expands up to 45%
when a person looks at something
pleasing. Write this percentage as a
fraction in simplest form.
=
=
......................................................................................
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page 83
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© Maths Mate 4.2/5.1 Skill Builder 12
Skill 12.9
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Writing a fraction as a percentage.
EITHER
• Find the equivalent fraction which has a
denominator of 100.
• The numerator of this fraction is the
equivalent percentage.
OR
100
• Multiply the fraction by
%
1
Example: 7 = 7 × 100 %
10 10
1
= 70%
7 × 10= 70 = 70%
Example:
10 × 10 100
Fraction ×
P = P%
100
11 11 × 5
=
A.
20 20 × 5
11
Q. Change
to a
20
percentage.
Simplify: ÷ 10
OR
100
% = Percentage
1
11 11 100 5
=
×
%
A.
20 1 20
1
55
=
100
= 11 × 5%
= 55%
Simplify: ÷ 20
= 55%
a) Change
1
to a
10
b) Change
percentage.
=
1 × 10
10
=
10 × 10 100
=
..............................................
d) Change
86
to a
100
=
10%
=
3
to a
5
=
..............................................
=
13
1
Change to a
3
percentage.
i)
=
..............................................
=
=
..............................................
k) Change
1
to a
100
=
..............................................
www.mathsmate.net
=
..............................................
2
Change to a
3
percentage.
l)
percentage.
=
=
..............................................
percentage.
Change
to a
20
percentage.
page 84
2
Change to a
5
percentage.
f)
3
to a
4
=
..............................................
=
h) Change
=
=
1
to a
2
=
..............................................
j)
=
percentage.
percentage.
=
=
e) Change
7
to a
25
percentage.
..............................................
..............................................
g) Change
c) Change
percentage.
percentage.
=
9
to a
50
=
=
..............................................
© Maths Mate 4.2/5.1 Skill Builder 12
MM4.2 1 1 2 2 3 3 4 4
MM5.1 1 1 2 2 3 3 4 4
Skill 12.10 Ordering decimal numbers.
•
•
•
•
Line up the decimal numbers at their decimal points.
Compare digits in the same places, starting from the left, until you find the smallest digit.
Hint: The number with the smallest digit will be the smallest number.
Look for the second smallest number.
Continue in this way until you find the largest number.
A. 0.07, 0.207, 0.27, 0.702
Q. Place in ascending order:
3rd
smallest 1st
2nd
largest 4th
a)
e)
.
.
.
.
.
T
2
0
2
7
H Th
7
7
0 7
0 2
Place in order from largest to smallest:
0.096, 0.69, 0.609, 0.09
U.
0.
0.
0.
0.
c)
U
0
0
0
0
te
nt
hu hs
n
th dre
ou dt
sa hs
nd
th
s
un
its
0.27, 0.07, 0.207, 0.702
T
0
6
6
0
H Th
9 6
9
0 9
9
Find the smallest digits.
Work from left to right.
Units:
all 0
Tenths:
0<2<7
so 0.07 is the smallest
0.702 is the largest
either 0.207 or 0.27 is the
2nd smallest
Hundredths: 0 < 7
so 0.207 is the 2nd smallest
0.27 is the 3rd smallest
b) Place in ascending order:
0.047, 0.74, 0.407, 0.074
U . T H Th
the largest number
the smallest number
Place in ascending order:
0.508, 0.08, 0.085, 0.58
d) Place in descending order:
Place in ascending order:
0.807, 0.07, 0.87, 0.087, 0.708
f)
0.135, 0.53, 0.105, 0.513
g) Place in order from largest to smallest:
0.239, 0.209, 0.093, 0.302, 0.3
page 85
Place in order from smallest to largest:
0.364, 0.063, 0.63, 0.34, 0.043
h) Place in ascending order:
0.156, 0.105, 0.51, 0.016, 0.065
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Skill 12.11 Comparing and ordering fractions.
•
•
•
Find the least common denominator of the fractions, which is the Lowest Common Multiple
(LCM) of the denominators.
Change the fractions to equivalent fractions with the lowest common denominator.
Arrange the fractions in order of the numerators (the smallest fraction has the smallest
numerator and so on).
smallest numerator
= smallest fraction
1 < 3 < 5
6
6
6
same denominator
Hint: If unsure which is the LCM of the denominators, use their product as the common
denominator. When the smaller denominators divide evenly into the biggest denominator,
this biggest number becomes the common denominator.
Q. Place in ascending order:
3 1 2
, ,
5 2 3
A.
1 3 2
, ,
2 5 3
3 1 2
, ,
5 2 3
LCM of 2, 5 and 3
is 2 × 5 × 3 = 30
3 × 6 18
=
5 × 6 30
1 × 15 15
=
2 × 15 30
2 × 10 20
=
3 × 10 30
a)
Which fraction has greater value?
3
2
or
8
5
c)
b) Which fraction has greater value?
5
5
or
11
8
LCM of 8 and 5 is 40
3 × 5 15 2 × 8 16
15 16
=
=
⇒ < ⇒
8 × 5 40 5 × 8 40
40 40
...............................................................................................
2
5
Which fraction has greater value?
...............................................................................................
d) Which fraction has greater value?
5
4
or
12
9
7
3
or
10
5
...............................................................................................
e)
...............................................................................................
Place in order from smallest to largest:
1 5 3
, ,
2 8 5
15 18 20
<
<
30 30 30
or 1 < 3 < 2
2 5 3
⇒ 15 < 18 < 20, so
f)
Place in order from largest to smallest:
5 4 9
, ,
6 5 10
LCM of 2, 8 and 5
is 8 × 5 = 40
1 × 20 20
5×5
=
=
2
8
× 20 40
×5
.................................................................................................................
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page 86
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© Maths Mate 4.2/5.1 Skill Builder 12
continues on page 88
Skill 12.12 Converting between decimals, fractions and percentages (1).
•
MM4.2 1 1 2 2 3 3 4 4
MM5.1 1 1 2 2 3 3 4 4
Convert between decimals, fractions and percentages. (see skills 12.4 to 12.9, pages 79 to 84)
÷ numerator by denominator
÷ 100%
Decimals
make denominator 100
and simplify
Percentages
× 100%
Fractions
×
100
%
1
For denominator put 1 followed by one zero
for each digit after the decimal point and simplify
Decimal
Percentage
13 13 × 2 26
=
=
50 50 × 2 100
= 26 ÷ 100
= 0.26
13 13 100 2
=
×
%
50 50
1
1
= 13 × 2%
= 26%
Decimal
0.26
a)
Complete the table:
Make denominator
a power of 10
Percentage
Fraction
13
50
A.
Simplify: ÷ 50
Fraction
13
50
Decimal
Q. Complete the table:
Percentage
26%
b) Complete the table:
Decimal
Fraction
Percentage
0.05
1
20
5%
Decimal
Fraction
Percentage
45%
5 ÷ 5 Simplify: ÷ 5
1
=
100 ÷ 5
20
...................................................................................................
...................................................................................................
0.05
= 0.05 × 100% = 5%
...................................................................................................
...................................................................................................
0.05 =
c)
Complete the table:
Decimal
Fraction
d) Complete the table:
Percentage
Decimal
0.6
Fraction
7
20
Percentage
...................................................................................................
...................................................................................................
...................................................................................................
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page 87
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© Maths Mate 4.2/5.1 Skill Builder 12
continued from page 87
Skill 12.12 Converting between decimals, fractions and percentages (2).
e)
Complete the table:
Decimal
Fraction
f)
Complete the table:
Percentage
Decimal
Fraction
0.07
...................................................................................................
...................................................................................................
...................................................................................................
...................................................................................................
Decimal
Fraction
h) Complete the table:
Percentage
Decimal
0.1
Fraction
3
10
Percentage
...................................................................................................
...................................................................................................
...................................................................................................
...................................................................................................
Complete the table:
Decimal
Fraction
j)
Complete the table:
Percentage
Decimal
Fraction
0.4
k)
Percentage
70%
g) Complete the table:
i)
MM4.2 1 1 2 2 3 3 4 4
MM5.1 1 1 2 2 3 3 4 4
Percentage
55%
...................................................................................................
...................................................................................................
...................................................................................................
...................................................................................................
Complete the table:
Decimal
Fraction
l)
Complete the table:
Percentage
Decimal
90%
Fraction
17
50
Percentage
...................................................................................................
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page 88
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© Maths Mate 4.2/5.1 Skill Builder 12
continues on page 90
MM4.2 1 1 2 2 3 3 4 4
MM5.1 1 1 2 2 3 3 4 4
Skill 12.13 Comparing decimals, fractions and percentages (1).
•
•
Convert the decimals, fractions and percentages to the same form, by writing all as
decimals, or as fractions, or as percentages. (see skill 12.12, page 87)
Compare the decimals, or the fractions, or the percentages.
Hint: The most convenient form is the decimal form. Write the fractions and percentages as
decimals.
Q. Which is greater?
A.
Write the fraction
as a decimal
Make denominator
a power of 10
= 25 ÷ 100
= 0.25
Write the percentage
as a decimal
Percentage
30
100
= 30 ÷ 100
= 0.3
30% =
Fraction
1
or 30%
4
1 1 × 25
=
4 4 × 25
25
=
100
1
0.3 is greater than 0.25, so 30% >
4
30% is greater.
a)
Which is greater?
0.07 or 70%
b) Which is greater?
20% or 0.25
70
= 70 ÷ 100 = 0.7
100
......................................................................................................
70% =
0.7
> 0.07
.................................................................................
c)
70%
Which is greater?
.................................................................................
d) Which is greater?
4
or 45%
5
9
or 9%
10
e)
......................................................................................................
......................................................................................................
......................................................................................................
.................................................................................
.................................................................................
Which is greater?
f)
Which is greater?
1
or 1%
10
2
or 25%
5
......................................................................................................
......................................................................................................
.................................................................................
.................................................................................
g) Which is greater?
5
0.6 or
6
h) Which is greater?
1
0.4 or
4
......................................................................................................
......................................................................................................
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page 89
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© Maths Mate 4.2/5.1 Skill Builder 12
continued from page 89
MM4.2 1 1 2 2 3 3 4 4
MM5.1 1 1 2 2 3 3 4 4
Skill 12.13 Comparing decimals, fractions and percentages (2).
i)
k)
Which is greater?
0.75 or 7.5%
j)
.......................................................................................................
.......................................................................................................
.................................................................................
.................................................................................
Which is greater?
l)
Which is greater?
3
or 30%
100
3
or 35%
5
.......................................................................................................
.......................................................................................................
.................................................................................
.................................................................................
m) Which is greater?
8
or 8%
10
n) Which is greater?
1
or 30%
3
.......................................................................................................
.......................................................................................................
.................................................................................
.................................................................................
o) Which is greater?
7
0.7 or
8
p) Which is greater?
4
0.9 or
5
.......................................................................................................
.......................................................................................................
.................................................................................
.................................................................................
q) Which is greater?
3
or 65%
4
s)
Which is greater?
0.5 or 5%
r)
Which is greater?
1
or 15%
5
.......................................................................................................
.......................................................................................................
.................................................................................
.................................................................................
Which is greater?
0.23 or
t)
3
20
Which is greater?
0.03 or
3
10
.......................................................................................................
.......................................................................................................
.................................................................................
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page 90
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© Maths Mate 4.2/5.1 Skill Builder 12