AnSWErS to tHE StudEnt'S Book ExErCiSES - Hodder Plus Home

Chapter 5Exercise 5.1 (page 73)1 5 2 3.84 3 4.54 3.45 5 9.2 6 62.417 1.20 8 2.68 9 4.4810 2.65 11 1.78 12 1.85Exercise 5.2 (page 76)1 Check students’ answers. Possible answersinclude the following.a) positive 3 negative 5 negativeb) Multiplying by number less than 1 shouldmake answer smallerc) 3 3 60 5 180 and answer should be morethan thisd) √ ___64 5 8 and answer should be less than this2 Check students’ answers. Possible answersinclude the following.a) Answer is too large, since 0.9 is near 1b) negative 4 negative 5 positivec) 6 2 5 36 and answer should be less than thisd) 8 1 3 5 11 so last digit should be 13 a) 1000 3 20 5 20 000b) 0.4 3 0.4 5 0.16c) 220 4 5 5 244 a) 7 3 £9 5 £63b) 30 3 £15 5 £450 or 30 3 £10 5 £300c) 3 3 £6 1 3 3 £2 5 £245 a) 62 067.5 4 81.4 5 762.5or 62 067.5 4 762.5 5 81.4b) √ _______1466.89 5 38.3 c) 17.6 3 3.8 5 66.88d) 278.93 1 18.2 5 297.13, 297.13 4 4.3 5 69.1or 297.13 4 69.1 5 4.36 a) 468.38 b) 6.807 a) 12.647 b) 896.8748 a) 61.1 b) 4.89 a) (i) 40 3 5 64 000(ii) 20 3 0.2 5 4(iii) √ _______7 2 2 4 2 5 √ _______49 2 16 5 √ ___33 < 6(iv) _______ 10 1 30.5 ____ 400.08 0.08 5 _____ 4000 5 5008b) (i) 60 236.288(ii) 3.496(iii) 5.93 (to 2 d.p.)(iv) 516 (to nearest whole number)Exercise 5.3 (page 82)1 a) 2 hours and 51 minutesb) 9 minutes2 a) 1.45 hours b) 0.9 hours3 3 hours and 15 minutes4 1 hour and 48 minutes5 56 £31.32 and £20.887 700 ml or 0.7 litre8 54 mph9 £191.11 or £191.1210 60 73611 200.8 (to 1 d.p.)12 2.2 g/cm 313 15.2 cmMixed exercise 5 (page 83)1 a) 3 b) 3.52 2.32 (to 2 d.p.)3 a) The answer should be more than 7 2 , whichis 49.b) Multiplying 2.4 by a number less than 1should give an answer less than 2.4.c) 120 3 49 < 120 3 50 5 6000, not nearly60 000 (or equivalent argument).d) The answer should be negative.4 a) 900 3 30 5 27 000b) 0.6 2 5 0.36c) 248 4 6 5 28 or 250 4 6 < 285 a) 1270.26 b) 2.886 a) (i) 20 3 5 8000 (ii) 30 3 0.3 5 9(iii) √ _______8 2 2 4 2 5 √ _______64 2 16 5 √ ___48 < 7(iv) _______ 30 1 505 ____ 800.04 0.04 5 2000b) (i) 9800.344(ii) 7.743(iii) 6.93 (to 2 d.p.)(iv) 2054 (to nearest integer)7 38 a) 3 hours 42 minutes b) 2 hours 45 minutesc) 48 minutes d) 51 minutes9 34.3 mph (to 1 d.p.)10 66 834 people11 £96.91 or £96.9212 2.9 cm (to 1 d.p.)Chapter 6Exercise 6.1 (page 88)1 a) £696.73 b) £18 310.68c) £3124.132 a) £91.75 b) £399.19 c) £512.333 £18 5754 £17.785 2340 rabbitsExercise 6.2 (page 91)1 a) £92 b) £47 c) £192.40 d) £358.602 a) £696 b) £123 c) £221.33 d) £392.153 £813.954 £75.055 £12 5006 £759 or £760 or £758.977 £34 440 or £34 439 or £34 439.25Higher WJEC GCSE Mathematics © 2010, Hodder EducationAnswers to the Student’s Book exercises 197