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7
Decimals and fractions
CHAPTER
7.1 Arithmetic of decimals
In a decimal number the decimal point separates the whole number part from the part that is less than 1
When adding or subtracting decimals line up the decimal points first.
To multiply by a decimal ignore the decimal point and do the multiplication with whole numbers.
Then decide on the position of the decimal point.
Example 1
a Multiply 5.12 by 4.6
Solution 1
51112
a
1 1 1 1
21146
3101712
210141810
213151512
Estimate 5 5
25
b
b Multiply 3.4 by 0.2
Ignore the decimal points and do the multiplication with whole numbers.
Round 5.12 to 5 and round 4.6 to 5
An estimate for the answer is 5 5
5.12 4.6 23.552
This means that the decimal point will go between the 3 and the 5 as 23.552 is close to 25
5.12 4.6 23.552
The number of decimal places in the answer is 3 which is the same as the total
number of decimal places in the question.
This rule is another way of finding the position of the decimal point in the answer.
314
212
618
3.4 0.2 0.68
Do the multiplication with whole numbers.
The total number of decimal places in the question is 2 so there must be 2 decimal
places in the answer.
To divide a number by a decimal multiply both the number and the decimal by a power of
10 (10, 100, 1000 …) to make the decimal a whole number. It is much easier to divide by a whole
number than by a decimal.
Example 2
Divide 20 by 0.4
Solution 2
10
200
20
0.4 4
50
0
0
4 2
So 20 0.4 50
92
10
To make 0.4 a whole number multiply it by 10
So multiply both 20 and 0.4 by 10
Then divide in the usual way.
7.1 Arithmetic of decimals
CHAPTER 7
Example 3
Divide 58.2 by 0.03
Solution 3
1191410
2
81
21
0
35
100
5820
58.2
0.03 3
100
To make 0.03 a whole number multiply it by 100
So multiply both 58.2 and 0.03 by 100
Then divide in the usual way.
So 58.2 0.03 1940
Exercise 7A
1 Write each of the following sets of numbers in order of size. Start with the smallest number
each time.
a 0.373 0.37 0.73 0.333 0.733
b 15.8 15.38 15.3 15.833 15.803
c 0.045 0.05 0.0545 0.055 0.0454
d 6.067 6.006 6.07 6.06 6.077 6.076
e 8.092 8.9 8.02 8.09 8.2 8.29 8.92
2 Work out
a 8.2 9.7
e 13.1 5.69
i 4 6.2 8.77
b 5.67 0.94
f 87.34 45.9
j 23 15.6 3.45
c 12.45 3.49
g 345.06 24.8
d 76.29 64.67
h 15.2 8.953
3 Work out
a 8.57 3.21
e 8.6 3.42
i 8.72 6.04
b 19.31 7.16
f 14.6 4.31
j 7.34 3.286
c 56.43 12.56
g 9 3.4
d 67.65 45.8
h 17 5.43
4 Work out
a 9.62 10
e 8.2 100
i 0.21 1000
b 67.231 100
f 0.9 100
j 6.08 100
c 0.83 10
g 8.41 100
k 0.0134 10
d 0.0065 1000
h 43.2 1000
l 56.1 100
5 Work out
a 6.34 0.4
e 2.16 0.3
b 4.21 0.3
f 0.54 0.8
c 0.02 0.4
g 0.723 0.06
d 0.08 0.3
h 3.15 0.8
6 Work out
a 3.1 4.2
e 8.6 2.4
b 0.36 1.4
f 9.2 0.15
c 3.6 2.3
g 0.064 0.73
d 7.4 0.53
h 0.095 3.4
7 Work out the cost of 0.6 kg of carrots at 25p per kilogram. Give your answer in pounds.
8 Work out the cost of 1.6 m of material at £4.20 per metre.
9 Work out
a 456 100
e 0.9 10
i 0.054 10
b 72.3 10
f 67.2 100
j 2.31 100
c 0.76 10
g 7 1000
k 45 1000
d 53 100
h 4 100
l 6.01 100
10 Work out
a 12 0.2
e 4.2 0.3
i 6.12 0.003
b 5 0.2
f 0.72 0.03
j 0.035 0.7
c 26 0.4
g 0.145 0.5
k 0.048 0.6
d 9 0.04
h 19.2 0.03
l 0.00828 0.09
93
Decimals and fractions
CHAPTER 7
11 Five people share £130.65 equally. Work out how much each person will get.
12 A bottle of lemonade holds 1.5 litres. A glass will hold 0.3 litres.
How many glasses can be filled from the bottle of lemonade?
7.2 Manipulation of decimals
8.4
Using a calculator 42
0.2
84
420 so multiplying the numerator by 10 without altering the denominator multiplies the
0.2
answer by 10
8.4
4.2 so multiplying the denominator by 10 without altering the numerator divides the
2
answer by 10.
0.84
4.2 so dividing the numerator by 10 without altering the denominator divides the
0.2
answer by 10.
8.4
420 so dividing the denominator by 10 without altering the numerator multiplies the
0.02
answer by 10.
Similar results are obtained by using other powers of 10
8400
For example 42 000 (the numerator 8.4 has been multiplied by 1000 without altering the
0.2
denominator, so the answer has been multiplied by 1000).
Sometimes the numerator and denominator are both changed.
8.4
84
For example starting with the result 42 it is possible to write down the value of 0.2
0.002
The numerator 8.4 has been multiplied by 10 and the denominator has been divided by 100 so the
84
answer has been multiplied by 1000, that is 42 000
0.002
Example 4
16.3
16.3
Given that 6.52 work out the value of 2.5
25
Solution 4
16.3
16.3
25
2.5 10
94
16.3
16.3
Starting with multiply the denominator by 10 to get 2.5
25
16.3
6.52 10
25
Multiplying the denominator by 10 without altering the numerator divides the answer by 10
16.3
0.652
25
To get the answer divide 6.52 by 10
7.2 Manipulation of decimals
CHAPTER 7
Example 5
3.46 25.5
Given that 25.95 find the value of each of the following.
3.4
34.6 2.55
a 0.34
2.595 0.34
b 25.5
3.46 10 25.5 10
34.6 2.55
3.4 10
0.34
3.46 25.5
Starting with multiply 3.46 by 10 and divide
3.4
25.5 by 10 (so the value of the numerator is not altered)
34.6 2.55
and divide the denominator by 10 to get 3.4
34.6 2.55
25.95 10
0.34
Dividing the denominator by 10 without altering the
numerator multiplies the answer by 10
34.6 2.55
259.5
0.34
To get the answer multiply 25.95 by 10
3.46 25.5 25.95 3.4
3.46 25.5
Multiply both sides of 25.95 by 3.4
3.4
25.95 3.4
3.46
25.5
Divide both sides of 3.46 25.5 25.95 3.4 by 25.5
Solution 5
a
b
25.95 10 3.4 10
2.595 0.34
25.5
25.5
25.95 3.4
Starting with divide 25.95 by 10 and divide 3.4
25.5
by 10 (so the value of the numerator is divided by 100 and
2.595 0.34
the denominator is not altered) to get 25.5
2.595 0.34
3.46 100
25.5
Dividing the numerator by 100 without altering the
denominator divides the answer by 100
2.595 0.34
0.0346
25.5
To get the answer divide 3.46 by 100
Exercise 7B
1 Given that 6.4 2.8 17.92 work out
a 64 28
b 640 2.8
c 0.64 28
d 0.64 0.028
c 0.183 1.25
d 0.183 12.5
c 0.132 55
d 0.0132 550
c 304 4.75
d 3.04 0.475
2 Given that 18.3 1.25 14.64 work out
a 183 1.25
b 1.83 1.25
3 Given that 13.2 5.5 72.6 work out
a 132 5.5
b 1.32 0.55
4 Given that 30.4 4.75 6.4 work out
a 30.4 47.5
b 3.04 4.75
95
Decimals and fractions
CHAPTER 7
23.2 5.1
5 Given that 34.8 work out
3.4
23.2 51
232 51
a b 3.4
3.4
23.2 5.1
c 34
232 51
d 34
17.2 4.5
6 Given that 32.25 work out
2.4
172 45
17.2 4.5
a b 2.4
240
17.2 45
c 240
1.72 0.45
d 0.24
7 Given that 23 56 1288 work out
a 0.23 560
b 1288 5.6
c 12.88 0.23
d 1288 (23 28)
8 Given that 52 32 1664 work out
a 0.52 0.32
b 1664 5.2
c 16.64 0.32
d 166.4 0.64
9 Given that 884 34 26 work out
a 8.84 340
b 884 2.6
c 8.84 260
d 884 (3.4 2.6)
10 Given that 1512 36 42 work out
a 15.12 3.6
b 1.512 0.036
c 15.12 420
d 1.512 0.84
144 28
11 Given that 96 work out
42
14.4 28
1.44 2.8
a b 0.42
420
14.4 2.8
c 9.6
4.2 9.6
d 0.028
84 45
12 Given that 108 work out
35
8.4 4.5
0.84 4.5
b a 350
0.035
8.4 0.45
c 10.8
10.8 0.35
d 840
1872
13 Given that 1300 work out
1.22
1872
18.72
a b 2
12
1.22
187.2
c 2
0.12
936
d 2
120
7.3 Conversion between decimals and fractions
A terminating decimal is a decimal which ends.
For example 0.56, 0.0004 and 4.57 are terminating decimals.
All terminating decimals can be converted to fractions using place value.
0.7 170
6
0.76 170 100
7
0
6
100 100
7
6
100
96
6
0.06 100
7.3 Conversion between decimals and fractions
Example 7
Write 0.024 as a fraction.
Give your fraction in its simplest form.
Write 3.7 as a fraction.
Solution 7
.
2
4
2
4
1000
3
The heading of the last
column with a figure in
it is thousandths, so the
denominator is 1000
2
4
0.024 1000
1
2
6
3
500 250 125
tent
hs
0
unit
s
hund
redt
hs
thou
sand
ths
0
tent
hs
unit
s
Solution 6
.
3.7 3170
hund
redt
hs
thou
sand
ths
Example 6
CHAPTER 7
7
The 3 is the whole number part, the .7 is 170
Example 9
All fractions can be changed into decimals.
Example 8
Write the following fractions as decimals.
2
3
b a 190
100
Solution 8
a 190 0.9
b
2
3
100
0.23
Write the following fractions as decimals.
b 1215
a 25
Solution 9
Method 1 (non-calculator using equivalent
fractions)
4
4
b 1215 a 25 140 0.4
100 0.44
Method 2 (calculator)
a 25 means 2 5
Using a calculator
b
1
1
25
means 11 25
Using a calculator
2 5 0.4
11 25 0.44
2
5
1
1
25
0.4
0.44
Short division is suitable for changing 25 to a decimal because the denominator is small.
2
5
means 2 5
2.0 is the same as 2 so divide 2.0 by 5
2
0. 4
2
.0
52
2
5
0.4
5 does not divide into 2 so put down a zero and carry.
5 divides into 20 four times.
Not all fractions can be written as terminating decimals.
For example 13 1 3 0.333 33 … which is a recurring decimal.
A recurring decimal is a decimal in which one or more figures repeat.
0.11111111 … , 0.565 656 56 … and 9.762 333 33 … are also recurring decimals.
To show that a figure recurs put a dot above the figure.
.
.
So 0.333 33 … is written as 0.3 and 13 0.3
Sometimes more than one figure recurs.
3 11 0.272 727 …
3
11
A dot is placed above each recurring figure.
..
So 131 0.27
97
Decimals and fractions
CHAPTER 7
Example 10
Write the following fractions as decimals.
b 1232
c 57
a 79
Solution 10
a 79 means 7 9
Work out 7 9 on a calculator.
Using a calculator
b
.
7 9 0.777 777 … 0.7
The 7 recurs so put a dot above the 7
1
3
22
Work out 13 22 on a calculator.
means 13 22
Using a calculator
c
..
13 22 0.590 909 0 … 0.59 0
The 90 recurs so put a dot above each of these figures.
Do not put a dot above the 5 as it does not recur.
5
7
Work out 5 7 on a calculator.
means 5 7
Using a calculator
.
.
5 7 0.714 285 714 … 0.714 285
A group of six figures recurs.
There isn’t enough room to see all the figures recurring but
you can see that the same pattern of figures is starting
again.
When more than two figures recur just two dots are used,
one above the first figure in the recurring group and one
above the last figure in the group.
Fractions written in their simplest form with denominators 2, 4, 5, 8, 10, 16, 20, … will convert to
terminating decimals.
Fractions written in their simplest form with denominators 3, 6, 7, 9, 11, 12, 13, 14, 15, 17, 18, 19, …
will convert to recurring decimals.
In general if a fraction written in its simplest form has a denominator with a prime factor other than
2 or 5, it will convert to a recurring decimal.
Example 11
Work out whether the following fractions will convert to terminating or recurring decimals.
b 3270
a 380
Solution 11
a 380 145
15 3 5
Write the fraction in its simplest form.
Write the denominator as the
product of its prime factors.
3 is a prime factor as well as 5
will convert to a recurring decimal.
8
30
b
7
20
Just consider the fraction part.
20 2 2 5
Write the denominator as the product of its prime factors.
The only prime factors are 2 and 5
7 will convert to a terminating decimal.
20
98
7.4 Converting recurring decimals to fractions
CHAPTER 7
The fractions and decimals in the table are some
that are used frequently and should be learnt.
Fraction
Decimal
1
100
1
10
1
5
1
4
1
3
1
2
2
3
3
4
0.01
0.1
0.2
0.25
.
0.3
0.5
.
0.6
0.75
Exercise 7C
1 Write each of the decimals as a fraction in its simplest form.
a 0.7
b 0.14
c 0.093
d 0.006
e 0.2
f 2.5
g 25.08
h 2.84
2 Write the following fractions as decimals.
3
7
3
b c a 190
100
100
e
8
1000
3 Write the following as equivalent fractions and then as decimals.
9
b 570 c 285 d a 45 10
100
100
500 1000
e
3
20
4 Write down the following fractions as decimals.
b 14
c 23
a 12
e
3
4
e
1
1
16
d
d
56
1
1000
1
5
100
5 Use short division to change these fractions to decimals.
b 38
c 16
a 35
6 Use a calculator to change these fractions to decimals.
2
3
b 490
c d 58
a 312
125
7 By writing the denominator in terms of its prime factors, decide whether the following fractions
will convert to recurring or terminating decimals.
6
b 1372
c 485
d 1432
e f 3670
a 490
125
8 Use a calculator to change these fractions to decimals.
b 89
c 151
d 172
a 56
e
2
7
7.4 Converting recurring decimals to fractions
All recurring decimals can be converted to fractions.
To convert a recurring decimal to a fraction:
● introduce a letter, usually x
● form an equation by putting x equal to the recurring decimal
● multiply both sides of the equation by 10 if 1 digit recurs, by 100 if 2 digits recur, by 1000 if 3
digits recur and so on
● subtract the original equation from the new equation
● rearrange to find x as a fraction.
99
Decimals and fractions
CHAPTER 7
Example 11
.
Convert the recurring decimal 0.2 to a fraction.
Solution 11
Let
x 0.2222 …
10x 2.222 …
10x 0.222 …
9x 2
x 29
.
0.2 29
Put x equal to the recurring decimal.
Multiply both sides of the equation by 10 as 1 digit recurs.
Subtract the equations.
Divide both sides by 9
Example 12
. .
Convert the recurring decimal 0.2371 to a fraction.
Solution 12
Let
x 0.237 137 1 …
1000x 237.1371 …
1000x 0.2371 …
999x 236.9
236.9
x 999
2369
9990
. . 2369
0.2371 9990
Put x equal to the recurring decimal.
Care is needed here, the 2 does not recur.
Multiply both sides of the equation by 1000 ( 103) as 3 digits recur.
Subtract the equations.
Divide both sides by 999
Multiply both the numerator and denominator by 10 to change the decimal
in the numerator to an integer.
Example 13
..
Convert the recurring decimal 3.08 6 to a fraction.
Solution 13
..
3.08 6 3 0.086 86…
Let
x 0.086 86 …
100x 8.686 ….
1000x 0.086 86…
99x 8.6
8.6
x 99
86
990
43
495
..
4
3
3.08 6 3
495
100
Consider the decimal part 0.086 86 …
Put x equal to the recurring decimal.
Care is needed here. The 0 does not recur.
Multiply both sides of the equation by 100( 102) as 2 digits recur.
Subtract the equations.
Divide both sides by 99
Multiply both the numerator and denominator by 10 to change
the decimal in the numerator to an integer.
Simplify the fraction.
Include the whole number part in the answer.
7.5 Rounding to significant figures
CHAPTER 7
Example 14
.
Given that 0.2 29
.
Express the recurring decimal 0.32 as a fraction.
Solution 14
.
.
0.32 0.3 0.02
.
0.3 0.2 10
130 29 110
To use the information given in the question split up the decimal 0.32222 … 0.3 0.02222 …
Rewrite the recurring part of the decimal using the given result.
Change all decimals to fractions.
130 920
2970 920
Write fractions with a common denominator so they can be added.
2990
.
0.32 2990
Exercise 7D
Convert each recurring decimal to a fraction. Give each fraction in its simplest form.
..
1 0.777 77 …
2 0.343 434 …
3 0.915 915 …
4 0.18
. .
.
..
..
5 0.317
6 0.05
7 0.326
8 0.701
.
..
..
.
9 0.23
10 6.83
11 2.106
12 7.352
..
..
13 Given that 161 0.54 write the recurring decimal 0.554 as a fraction.
..
..
14 Given that 353 0.15 write the recurring decimal 0.215 as a fraction.
.
.
15 Given that 16 0.16 write the recurring decimal 0.4016 as a fraction.
7.5 Rounding to significant figures
A number rounded to one significant figure has only one figure that is not zero.
5937 rounded to one significant figure is 6000
0.006 183 rounded to one significant figure is 0.006
A number rounded to two significant figures is more accurate than a number rounded to one
significant figure.
To round 5937 to two significant figures look at the third figure (3). As this is less than 5, do not
change the previous figure (9) and write zeros in the tens column and the units column.
So 5937 rounded to two significant figures is 5900
To round 0.006 183 to two significant figures, look at the third figure (8) after the zeros at the
beginning. As this is more than 5, increase the previous figure (1) by 1. Remember to include the
zeros at the beginning in your answer.
So 0.006 183 rounded to two significant figures is 0.006 2
To round whole numbers greater than one to three significant figures, look at the fourth figure.
101
Decimals and fractions
CHAPTER 7
To round decimals to three significant figures, look at the fourth figure after the zeros at the
beginning.
5937 rounded to three significant figures is 5940
0.006 183 rounded to three significant figures is 0.006 18
Example 15
Round
a 3462 to one significant figure
c 0.3469 to three significant figures
Solution 15
a 3462
3462 rounds to 3000 to one
significant figure.
b 7.38
7.38 rounds to 7.4 to two
significant figures.
c 0.3469
0.3469 rounds to 0.347 to three
significant figures.
d 0.0201
0.0201 rounds to 0.020 to two
significant figures.
b 7.38 to two significant figures
d 0.0201 to two significant figures
The second figure is 4. As this is less than 5, the 3 stays as it
is and a zero goes in all the other places.
The third figure is 8
As this is more than 5, increase the 3 by 1
The fourth figure after the zero at the beginning is 9
As this is more than 5, increase the 6 by 1
The third figure after the zeros at the beginning is 1
As this is less than 5, the zero before the 1 stays as it is.
The zero at the end is needed as it is the second significant
figure.
Example 16
6.73 4.5
Use your calculator to work out the value of 12.03 9.73
Give your answer correct to two significant figures.
Solution 16
6.73 4.5 11.23
Use a calculator to work out the value of the numerator.
12.03 9.73 2.3
Use a calculator to work out the value of the denominator.
11.23 2.3 4.882 608 696 …
The line in a fraction means divide.
Now use a calculator to work out 11.23 2.3
Write down all the figures shown on your calculator.
4.882 608 696 4.9 correct
to two significant figures
To give the answer to two significant figures, look at the third figure (8).
As this is more than 5, increase the figure before it by 1
Exercise 7E
102
1 Round these numbers to one significant figure
a 8234
b 76 420
e 0.381
f 0.004 56
c
g
453
0.109
d
h
72
532.4
Chapter summary
CHAPTER 7
2 Round these numbers to two significant figures
a 4263
b 8719
c
e 798
f 0.005 62
g
685
703
d
h
3.84
0.4032
3 Round these numbers to three significant figures
a 8736
b 56.24
c
e 0.030 56
f 87.98
g
27.839
6 735 412
d
h
0.786 21
907.189
d
h
l
82.14 (2)
0.002 345 1 (2)
0.000 481 6 (3)
4 Round these to the number of significant figures given in the brackets
a 6712 (1)
b 8614 (3)
c 6926 (2)
e 876.3 (3)
f 12.52 (3)
g 0.0426 (1)
i 7.6024 (3)
j 8.795 (2)
k 508 342 (3)
5 Use your calculator to work out the value of the following.
Give each answer correct to three significant figures.
a 5421 23
b 423 871
d
3250 720
0.32
e
9.6
13.21 9.1
c
0.0562 0.041
f
27.31 8.96
4.56 9.8
Chapter summary
You should now know that:
in a decimal number the decimal point separates the whole number part from the part that is
less than one
to multiply by a decimal ignore the decimal point and do the multiplication with whole
numbers. Then decide on the position of the decimal point
to divide by a decimal write the division as a fraction then multiply numerator and
denominator by a power of 10 to find an equivalent fraction with an integer as the
denominator
if a number in the numerator of an expression is multiplied by a power of 10 (or a number in
the denominator is divided by a power of 10) then the value of the expression is multiplied by
the same power of 10
if a number in the numerator of an expression is divided by a power of 10 (or a number in the
denominator is multiplied by a power of 10) then the value of the expression is divided by the
same power of 10
terminating decimals can be converted to fractions by using place value
fractions can be converted to decimals by using equivalent fractions or division
some fractions convert to recurring decimals
when the denominator of a fraction written in its simplest form has prime factors containing
only 2s andor 5s then the fraction will convert to a terminating decimal;
otherwise the fraction will convert to a recurring decimal
every recurring decimal can be converted to a fraction
numbers can be rounded to significant figures.
103
Decimals and fractions
CHAPTER 7
Chapter 7 review questions
1 Work out
a 5.6 10
d 0.0062 100
b 76.2 100
e 0.87 1000
c 9 100
2 Work out
a 0.2 0.3
d 0.4 0.08
b 1.2 0.6
e 6.1 4.2
c 0.37 0.5
f 0.32 5.6
3 Work out
a 6.25 0.5
d 56 0.2
b 75.6 0.3
e 46.2 0.03
c 47.7 0.09
f 0.84 0.004
4 0.3
0.06
0.058
0.26
a Write these four decimals in order of size. Start with the smallest decimal.
b Write 0.3 as a fraction.
c Work out 0.3 0.26
d Work out 0.058 100
5 a Work out 41.3 100
b Work out 0.4 0.6
(1388 January 2002)
c Work out 5.2 1.37
(1388 March 2003)
6 Change 78 to a decimal.
7 Karen says that 1234 can be converted into a terminating decimal. Lucy says that the fraction
converts to a recurring decimal. Who is correct? You must give a reason for your answer.
8 By writing the denominator as the product of its prime factors, decide whether the following
fractions will convert to a recurring decimal or a terminating decimal.
b 3575
c 725
d 1996
a 196
9 a Write 0.35 as a fraction. Give your answer in its simplest form.
b Write 38 as a decimal.
10 Use your calculator to write each fraction as a decimal.
b 1116
c 191
a 2430
11 1.54 450 693
Use this result to write down the answer to
a 1.54 45
b 1.54 4.5
c 0.154 0.45
12 Using the information that 97 123 11 931 write down the value of
a 9.7 12.3
b 0.97 123 000
c 11.931 9.7
(1387 June 2002)
d
7
90
(1387 May 2002)
(1387 June 2003)
13 a Express 49 as a recurring decimal.
..
b Convert the recurring decimal 0.136 to a fraction in its simplest form.
14 a Change 131 to a decimal.
..
b Prove that the recurring decimal 0.39 1333
104
(1387 June 2005)
Chapter 7 review questions
CHAPTER 7
.
15 Express the recurring decimal 2.06 as a fraction.
Write your answer in its simplest form.
(1388 March 2005)
16 Change to a single fraction
..
a the recurring decimal 0.13
..
b the recurring decimal 0.513
(1388 March 2002)
17 a is an integer such that 1 a 9
b is an integer such that 1 b 9
..
ab
Prove that 0.0ab 990
..
18 a Express 0.27as a fraction in its simplest form.
b x is an integer such that 1 x 9
..
x
Prove that 0.0x 99
..
19 a Convert the recurring decimal 0.36 to a fraction.
..
b Convert the recurring decimal 2.136 to a mixed number.
Give your answer in its simplest form.
..
20 The recurring decimal 0.72 can be written as the fraction 181
..
Write the recurring decimal 0.572 as a fraction.
(1388 January 2003)
(1388 March 2004)
(1387 November 2005)
21 Round the following to the number of significant figures given in the brackets
a 3546 (1)
b 3546 (2)
c 0.005 62 (1)
d 23.76 (2)
e 2.4387 (3)
f 696 213 (2)
105