MATHEMATICS
TH
4 EDITION
INSTRUCTOR’S MANUAL
WORKED SOLUTIONS TO THE ASSIGNMENTS
JOHN BIRD
, CONTENTS
Page
ASSIGNMENT 1 (chapters 1 to 4) 1
ASSIGNMENT 2 (chapters 5 to 8) 8
ASSIGNMENT 3 (chapters 9 to 12) 14
ASSIGNMENT 4 (chapters 13 to 16) 20
ASSIGNMENT 5 (chapters 17 to 20) 26
ASSIGNMENT 6 (chapters 21 to 23) 35
ASSIGNMENT 7 (chapters 24 to 26) 42
ASSIGNMENT 8 (chapters 27 to 31) 47
ASSIGNMENT 9 (chapters 32 to 35) 56
ASSIGNMENT 10 (chapters 36 to 39) 60
ASSIGNMENT 11 (chapters 40 to 43) 68
ASSIGNMENT 12 (chapters 44 to 46) 75
ASSIGNMENT 13 (chapters 47 to 49) 80
ASSIGNMENT 14 (chapters 50 to 53) 84
ASSIGNMENT 15 (chapters 54 to 58) 90
ASSIGNMENT 16 (chapters 59 to 61) 97
LIST OF FORMULAE 103
ASSIGNMENT 1 (Page 33)
, This assignment covers the material contained in Chapters 1 to 4.
2 1 1 ⎛1 1⎞ 7
Problem 1. Simplify (a) 2 ÷ 3 (b) ÷ ⎜ + ⎟ + 2
3 3 ⎛4 1⎞ ⎝3 5⎠ 24
⎜ × 2 ⎟
⎝7 4⎠
Marks
2 1 8 10 8 3 8 4
(a) 2 ÷ 3 = ÷ = × = = 4
3 3 3 3 3 10 10 5
1 ⎛1 1⎞ 7 1 ⎛ 5 + 3⎞ 7
(b) ÷ ⎜ + ⎟ + 2 = ÷ ⎜ ⎟ + 2 2
⎛4 1⎞ ⎝3 5⎠ 24 ⎛ 4 9⎞ ⎝ 15 ⎠ 24
⎜ × 2 ⎟ ⎜ × ⎟
⎝7 4⎠ ⎝7 4⎠
1 8 7
= ÷ + 2
9 15 24
7
7 15 7
= × + 2 1
9 8 24
35 7 11 7
= + 2 = 1 + 2
24 24 24 24
18 3
= 3 = 3 2
24 4
total : 9
Problem 2. A piece of steel, 1.69 m long, is cut into three pieces in the ratio 2
to 5 to 6. Determine, in centimetres, the lengths of the three pieces.
Marks
Number of parts = 2 + 5 + 6 = 13
169
. 169
Length of one part = m = cm = 13 cm 1
13 13
Hence 2 parts ≡ 2 × 13 = 26
5 parts ≡ 5 × 13 = 65
6 parts ≡ 6 × 13 = 78
i.e. 2 : 5 : 6 :: 26 cm : 65 cm : 78 cm 3
total : 4
1
576.29
Problem 3. Evaluate (a) correct to 4 significant figures
19.3
(b) correct to 1 decimal place