Cambridge Checkpoint Mathematics Revision Guide For the Cambridge Secondary 1 Test Answers 1 Place value, ordering and rounding Check your understanding 1.1 Check your understanding 1.4 1 623 < 652 1 18.6 2 304.8 2 3108 < 3112 3 8.07 4 28.222 3 0.235 > 0.215 5 61.46 6 72.20 4 9740 < 12 350 7 3.142 8 1.4 5 13.226 > 12.895 9 0.07 10 7.071 Check your understanding 1.2 Check your understanding 1.5 1 3620 2 1370 1 3.1 2 156.1 3 122 000 4 140 3 166 4 154 300 5 180 6 60 000 5 16 300 6 900 7 740 000 7 2520 8 0.0032 8 3000 9 540 10 13 000 Check your understanding 1.3 9 0.010 10 1 Check your understanding 1.6 1 2530 1 200 × 40 = 8000 2 4800 2 50 × 20 = 1000 3 90 3 2000 ÷ 50 = 40 4 260 4 600 ÷ 30 = 20 5 300 5 70 × 20 = 1400 g 6 6820 6 500 ÷ 20 = 25 7 12 400 people. 7 60 ÷ 4 = 15 8 $123 000 8 40 000 ÷ 200 = 200 9 $600 000 ÷ 30 = $20 000 10 20 × 10 = 200 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 1 l ANSWERS Spotlight on the test (page 5) 1 a) b) c) d) 7325 > 7236 20 × 1000 = 200 × 100 29 × 59 < 31 × 61 40 000 ÷ 100 > 400 ÷ 10 4 a) 15.604 b) 15.6 5 a) 300 and 20 b) 300 × 20 = 6000 6 a) 365 days in a year, 24 hours in a day, 60 minutes in an hour, 60 seconds in a minute b) 8000 c) 4000 d) 30 million 2 10 000 3 9285 2 Integers, powers and roots Check your understanding 2.1 Check your understanding 2.4 1 a) (+5) = 5 b) (+7) = 7 c) (+1) = 1 2 a) (–7) = –7 b) (–4) = –4 c) (–2) = –2 3 a) (+4) = +4 b) (–2) = –2 c) (–7) = –7 1 a) b) c) d) 4 a) (–10) = –10 b) (–2) = –2 c) (–1) = –1 2 14 32 × 5 22 × 11 23 × 32 22 × 32 × 5 5 a) (–0.4) = –0.4 b) (–1.6) = –1.6 c) 0 3 315 6 a) (+0.7) = 0.7 c) (+4.1) = 4.1 b) (–4.0) = –4.0 4 a) 120 = 23 × 3 × 5 and 144 = 24 × 32 b) 24 7 a) (+14.4) = 14.4 b) 0 c) (–3.9) = –3.9 5 a) 75 = 3 × 52 and 120 = 23 × 3 × 5 b) 600 8 (–4), (–3), (+6) 9 (–10), (–5), (–1), (+2) Check your understanding 2.5 10 (–10), (–8), (–5), (+1) Check your understanding 2.2 1 a) 12, 15 b) 10, 15 c) 11, 13, 17 1 a) 121 b) 216 c) 12 d) 4 2 a) 81 b) 512 c) 17 d) 9 3 a) 169 b) 125 c) 19 d) 3 2 5 4 343 3 6 5 102 = 100 and 112 = 121. 105 does lie between these values, so its square root lies between 10 and 11. 4 a) 37 c) No – 51 is 3 × 17 b) 41, 43, 47 d) 8 6 52 = 25, 62 = 36, 72 = 49 and 36 < 43 < 49 so Anton is right. Check your understanding 2.3 1 a) –14 b) –12 c) 18 d) 18 2 a) –5 b) –4 c) 2 d) –15 3 a) –48 b) –4 c) 36 d) 10 2 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 ANSWERS l Check your understanding 2.6 1 39 2 65 43 22 3 4 5 512 7 6 4 –1 812 8 9 45 56 10 101 or just 10 11 65 12 73 13 39 14 1 15 3 16 –3 Check your understanding 2.7 1 34 2 64 3 11 4 2 Spotlight on the test (page 12) 1 a) 24 b) 20 c) 23 2 260 ºC 3 25 July 4 a) Wednesday b) 6 ºC 5 a) 72 = 49, 82 = 64 and 49 < 60 < 64 b) 73 = 343 and 83 = 512; 250 does not lie between these values. 6 a) a = 4 b) b = –3 c) c = 0 b) 28 c) 1 7 41 8 a) 512 9 46 10 12 5 77 6 29 7 15 8 3 9 8 10 4 3 Expressions, equations and formulae Check your understanding 3.1 Check your understanding 3.3 1 expression 2 formula 1 2x + 8 2 3x + 6 3 equation 4 expression 3 10x – 5 4 7a + 35 5 formula 6 expression 5 20b – 30 6 12x + 8y 7 formula 8 expression 7 2x – 6y 8 8x + 12y 9 equation 10 formula Check your understanding 3.2 1 x9 2 y4 3 z6 4 x7 5 y4 6 1 9 18a – 27b 10 20b + 50 11 9x + 14 12 5x + 4 13 44x + 17 14 17y – 5 15 3x + 3y 16 2x + 6 17 9m 18 4n – 5 19 16k + 5 20 p + 3 7 y3 8 z9 9 m–2 10 z2 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 3 l ANSWERS Check your understanding 3.4 1 7(x + 3) 2 2(2y + 5) 3 5(z – 4) Check your understanding 3.6 1 5 8 2 5x 8 3 7 20 4 7x 20 5 5y 21 6 a 5 7 17b 30 8 7c 20 9 5x + 12 8 10 5y + 22 8 4 3(3x + 5) 5 5(3y – 5) 6 x(x + 7) 7 3y(y – 3) 8 5y(2y + 5) 9 3z(4z – 5) 10 2x(2y – 5) Check your understanding 3.5 V ac 1 b= 2m= y–c x 3r= C 2p 11 4T= PV R 12x – 5 20 12 5h= √ W8 11 2x –– Spotlight on the test (page 17) 6 n = u – 2a 1 a) expression b) formula c) equation u–n 7a= 2 8a= 9r= F m 2 4x 2 + 20x √p 4 2m(3m + 4n) –A– 3 2x 2 – 5x – 3 10 u = √ v2 – 2as 5 a) y 7 b) x5 6s= v2 – u2 2a 7x= y–9 3 8 a) B and E 9 10 4 c) z8 b) A, C and D 7x 8 3x + 1 10 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 ANSWERS l 4 Shapes, congruency and geometric reasoning Check your understanding 4.1 Check your understanding 4.3 1 Congruent – ASA Interior/exterior angles in polygons 2 Not congruent 1 a) 6 3 Congruent – SAS 2 36° 4 Congruent – RHS 3 140° 5 Annie is wrong – the shapes are similar but not congruent. 4 24 sides Check your understanding 4.2 1 Two lines of symmetry, and rotation symmetry of order 2. b) 60° c) 120° 5 45 sides Spotlight on the test (page 21) 1 Congruent – SSS 2 No lines of symmetry, and rotation symmetry of order 2. 2 Congruent – RHS 3 One line of symmetry, no rotation symmetry. 4 3 Not congruent 4 No lines of symmetry, and rotation symmetry of order 2. 5 One line of symmetry, no rotation symmetry. 6 No lines of symmetry, and rotation symmetry of order 2. 5 a) Order 4 b) No reflection symmetry 6 x = 150° and y = 30° 7 More than one plane of symmetry. 8 No plane of symmetry. 9 More than one plane of symmetry. Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 5 l ANSWERS 5 Measures and motion Check your understanding 5.1 Check your understanding 5.4 1 a) 160 cm b) 2.5 litres c) 3500 grams 2 a) 3.5 m b) 750 ml c) 0.65 kg 1 a) b) c) d) 70 litres 10 litres The minibus stopped for half an hour The minibus stopped to refuel 6 15 kg 2 a) b) c) d) A $14 000 $6000 2009 Check your understanding 5.2 Spotlight on the test (page 26) 1 115 km per hour 1 7.5 kg 2 8 m per second 2 325 cm 3 16 miles per hour 3 25 miles 4 a) 1000 m or 1 km b) 60 km per hour 4 a) S travels at 100 km per hour, so is breaking the rule. T travels at just under 90 km per hour so is not breaking the rule. b) Train T passes train S which is stationary but travelling in the opposite direction. 3 72 km 4 15 cm 5 190 miles 5 a) A 3.6 m/h, B 3.8 m/h, C 3.4 m/h, D 3.3 m/h b) Snail B is the fastest. Check your understanding 5.3 1 A 60 km h–1, B 0, C 20 km h–1, D 180 km h–1, E 8 m s–1, F 4 m s–1, G 2 m s–1. 2 a) 48 km h–1 5 a) Down b) 20 minutes c) 1520 b) 30 minutes c) 32 km h–1 6 Planning, collecting and displaying data Check your understanding 6.1 Check your understanding 6.2 1 Discrete. 1 Better to replace with (for example) more than 5 times a week, 2 to 4 times a week, and fewer than 2 times a week. 2 Continuous. 3 Continuous. 4 Discrete. 5 Continuous. 6 2 No improvement needed. 3 $10 and $20 are members of two different categories – ambiguous. Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 ANSWERS l Check your understanding 6.3 Spotlight on the test (page 30) 1 a) 13 1 Remove overlapping options, that is 1–5, 6–10, 11–15, >15 Allow option to reply 0. 2 4 5 6 7 8 9 b) 43 c) 43 – 8 = 35 8 Key 7 1 = 71 3 7 2 5 8 1 1 4 2 a) 1 2 3 4 5 4 3 Check your understanding 6.4 1 a) 3 3 1 4 7 1 6 5 8 9 key 1 9 = 19 2 b) 52 is very different from the rest. 3 a) Age n of child, in years Frequency 2 5 ≤ n < 10 4 13 ≤ t < 14 5 10 ≤ n < 15 7 14 ≤ t < 15 3 15 ≤ n < 20 9 15 ≤ t < 16 1 20 ≤ n < 25 8 1 25 ≤ n < 30 5 Time t, in seconds Frequency 12 ≤ t < 13 16 ≤ t < 17 b) 2 b) 6 10 Frequency Frequency 8 4 2 0 11 13 15 17 6 4 2 0 Time (s) 2 Categorical data: a pie chart would be suitable (or a bar chart). 10 20 Age (years) 30 c) A pie chart is unsuitable as this is not categorical data. 7 Equations, functions and inequalities Check your understanding 7.1 Check your understanding 7.2 1x=7 2 x=8 1 x = 3, y = 1 2 x = 4, y = 2 3 x = 17 4 x = 0.5 3 x = 6, y = 3 4 x = 3, y = –1 5 x = 10 6 x=3 5 x = 7, y = 3 6 x = 6, y = 4 7x=1 8 x=5 7 x = 2, y = –1 8 x = 1, y = 1 9x=1 10 x = 4 11 x = 4 12 x = 3 13 x = 5 14 x = 8 15 x = 2 16 x = 2 9 x = 3, y = –2 10 x = 7, y = 0 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 7 l ANSWERS Check your understanding 7.3 Check your understanding 7.5 1 a) 3x – 10 = 2(x + 1), b) x = 12, c) 26 by 48 1 x 2 + 7x + 12 2 y2 + 8y + 12 2 a) y + y – 6 + 2y – 2 = 40, b) y = 12 3 x 2 – 5x – 14 4 y2 + y – 20 3 a) 3x – 2 + 4x + 2 + x + 7 = 39, b) x = 4, c) 10, 18, 11 5 x 2 – 9x – 22 6 x 2 – 36 7 y2 – 9 8 y2 + 5y + 6 4 a) C = 12n + 10, b) nine people Check your understanding 7.4 1x<4 9 2x 2 + x – 1 10 2x 2 – x – 6 11 3x 2 – 5x + 2 12 3x 2 + 8x – 3 13 4x 2 + 8x + 3 14 6x 2 – 7x – 3 15 6x 2 + 13x + 6 16 9x 2 – 4 2x≤6 Spotlight on the test (page 36) 3y<5 4x≤4 1 x=3 5x≤1 2 x = 5, y = 1 6x<4 3 10y + 30 7x<5 4 x = 3 so shape A has side 8 and shape B side 6 8x≤7 9 5 1, 2 and 3 4 6 8 10 12 6 a) 6 < x ≤ 10 b) 10 2 4 6 8 6 8 10 7 x 2 + 2x – 15 11 2 4 6 8 8 6x 2 + 7x – 3 12 2 4 6 13 3, 4, 5, 6 and 7 14 3, 4, 5, 6 and 7 15 2, 3, 4, 5, 6, 7, 8 and 9 16 19 8 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 ANSWERS l 8 Measurement and construction Check your understanding 8.1 Spotlight on the test (page 38) This is a construction exercise, so there are no numerical solutions. 1 1 5 cm 4 cm 7 cm 5 cm 2 2 4 cm 3 cm 6 cm 5 cm 5 cm 9 cm 3 3 6 cm 4 cm 8 cm 7 cm Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 9 l ANSWERS 4 5 cm 5 cm 5 cm 5 cm 5 cm 5 cm 5 The correct order of instructions is: l Draw two straight lines BA and BC meeting at a point B. l Use compasses to draw the arc DE centred on B. l Use compasses to draw two arcs (with the same radii) centred on D and E. l The two arcs centred on D and E cross each other (intersect) at F. l Use a ruler to draw a straight line passing through B and F. 9 Pythagoras’ theorem Check your understanding 9.1 Check your understanding 9.2 1 13 cm 2 17 cm 1 1.5 cm 2 7.5 cm 3 12.5 cm 4 2.5 cm 3 8 cm 4 20 cm 5 11.4 cm 6 8.5 cm 5 6.2 cm 6 8.0 cm 7 9.9 cm 8 41 cm 7 5.6 cm 8 6 cm Spotlight on the test (page 40) 10 1 a = 13.6 cm c = 13 cm b = 5.2 cm d = 11.6 cm 2 j = 12 cm k = 20 cm Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 ANSWERS l 10 Transformations Check your understanding 10.1 Spotlight on the test (page 44) 1 Centre (0, 1) scale factor × 3 1 2 Scale factor × 4 Check your understanding 10.2 1 a) Translation [ 42 ] b) Reflection in line y = –1 c) Rotation 90° anticlockwise, about O. 8 6 4 S 2 0 R 2 4 6 2 Rotation 180° about O. 8 10 6 2 a) b) A 4 T –6 –4 2 –2 0 –2 2 4 6 B –4 –6 c) 180° rotation about (5, 1) 3 Enlargement by scale factor ×6, centre (0, 3). Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 11 l ANSWERS 11 Averages and spread Check your understanding 11.1 Check your understanding 11.3 1 a) 15.6 b) 7 1 The average age of both clubs is similar. The spread of the ages is much smaller in the squash club. 2 Mean 19.5, median 18, mode 17 and range 15 3 a) 15 b) 0 c) median Spotlight on the test (page 48) Check your understanding 11.2 1 Mean = 1.875 1 a) 14.5 years b) 15.5 years c) 16 years d) 7 years e) Decrease, as 13 < 14.5 2 3, 3, 7, 8, 10 2 a) Mean = 61.5 mm b) Modal class is 60 < t ≤ 90 3 a) 29 b) 36 c) Mr Hindocha’s class has done better – they have a higher median score. 12 Processing and presenting data Check your understanding 12.1 2 1 mall black station 90° 60° 216° 144° 126° 84° blond cinema brown 9 8 7 6 5 4 3 2 1 0 station 12 cinema Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 mall ANSWERS l Check your understanding 12.2 1 A – 3 B – 1 C – 2 2 C Spotlight on the test (page 52) 1 2 gold coaches lorries 150° 40° no award 90° 200° 120° silver 60° 60° bronze cars 3 a) 20 16 English 12 8 4 0 4 8 12 16 20 Maths b) Positive correlation c) Chloe might have scored 18 in Maths (or 17, or 19, depending on how you judge the correlation graph). Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 13 l ANSWERS 13 Fractions, decimals and percentages Check your understanding 13.1 1 a) 2 3 b) 23 24 c) 17 20 d) 5 6 2 a) 1 4 b) 1 5 c) 17 30 d) 1 4 3 a) 5 4 a) 3 4 2 11 5 a) 9 13 b) 1 b) 1 2 c) 8 2 3 b) 10 12 7 12 d) 1 Spotlight on the test (page 56) 1 1 6 c) 4 15 5 12 d) c) 4 5 d) 1 13 13 20 2 1 12 3 80% 4 60 5 $510 6 a) 1.65 b) $9.90 c) $8.00 Check your understanding 13.2 1 80% 2 85% 3 180 4 276 5 $102 6 $37 14 Sequences, functions and graphs Check your understanding 14.1 Check your understanding 14.2 1 a) b) c) d) 1 a) y = x + 1 11, 13, rule 2n – 1 16, 22, not arithmetic 37, 41, rule 4n + 17 7, 6, rule 12 – n 2 2, 7, 22, 67 3 5, 8, 13 b) y = 3x + 2 c) y = 5 – x Spotlight on the test (page 59) 1 A = R, B = P, C = S, D = Q 2 a) 3n + 4 b) 154 3 A = 2, B = 3, C = 1 4 y = 3x + 4 14 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 ANSWERS l 15 Angle properties Check your understanding 15.1 Check your understanding 15.3 1 a = 40°, b = 140°, c = 100°, d = 40° 1 w = 44°, x = 80°, y = 53°, z = 80° 2 p = 30°, q = 30°, r = 80°, s = 140° 2 40° 3 t = 61° 3 135° Check your understanding 15.2 4 57 + 63 + 70 = 190° not 180° as it should be for a triangle 1 a = 72° (alternate), b = 130° (corresponding), c = 120° (alternate), d = 60° (angles on a straight line), e = 51° (alternate), f = 129° (angles on a straight line), g = 115° (corresponding), h = 82° (alternate) Spotlight on the test (page 63) 2 a) Alternate 3 a = 44°, b = 81°, c = 60°, d = 39°, e = 141°, f = 103°, g = 77°, h = 38°, i = 142°, h = 38° b) Corresponding 3 a = 86° (alternate), b = 41° (alternate) 1 x = 51°, y = 132° 2 Alternate 16 Area, perimeter and volume Check your understanding 16.1 Check your understanding 16.3 1 28 cm2 1 A yes, B no, C yes, D yes, E no 2 14 cm2 2 3 6 cm 3 cm 12 cm2 4 4 cm2 3 cm 5 45 cm2 6 8 cm2 3 cm 6 cm Check your understanding 16.2 1 70 cm2 2 48 cm2 3 40 cm2 4 75 cm2 Check your understanding 16.4 1 6 + 6 + 30 + 40 + 50 = 132 cm2 2 2 × (24 + 36 + 54) = 228 cm2 Check your understanding 16.5 1 72 cm2, 70 cm2 2 x = 20, y = 8 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 15 l ANSWERS Check your understanding 16.6 Spotlight on the test (page 69) 1 550 mm2 1 a) 28 cm 2 60 000 cm3 2 a) Cuboid 3 12 m2 4 b) 36 cm2 b) 0.0075 m3 3 cm 5 a) 600 cm2 b) 0.06 m2 6 1 000 000 000 2 cm 2 cm 3 cm 2 cm 4 cm c) 2 × (12 + 6 + 8) = 52 cm2 d) 24 cm3 3 25 000 mm2 4 a) 6 cm 4 cm 6 cm 6 cm 10 cm 8 cm 10 cm 10 cm b) 24 + 24 + 24 + 32 + 40 = 144 cm2 17 Ratio and proportion Check your understanding 17.1 Check your understanding 17.3 1 a) 4:7 1 45 kilometres b) 3:4 c) 7:11 d) 5:6 2 60 cm and 100 cm 2 12.5 kg 3 80 birch and 120 beech 3 $192 4 $875 Check your understanding 17.2 1 40 minutes Spotlight on the test (page 72) 2 120 minutes 1 4 : 5 2 $80 3 3 34 hours 3 a) 36 4 a) €300 b) 6 b) £375 4 6 days 5 8 hours 5 9 hours 6 720 g 7 32 minutes 8 $7.68 16 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 ANSWERS l 18 Formulae, functions and graphs Check your understanding 18.1 Spotlight on the test (page 77) 1 24 2 1300 3 23 4 50 1 a) 27 b) 9 2 a) 600 b) 5 5 17 6 120 7 4 8 5 9 5 10 28 3 4.1 Check your understanding 18.2 1 1.5 2 8.1 3 2.8 4 0.9 8 0.3 9 2.7 10 3.1 5 a) T b) Q and R c) S 6 a) b) c) d) 5 3.7 6 1.6 7 2.6 4 a) y = 1.2x – 3 b) 1.2 c) –3 B A 8 seconds B, because after 500 m it is in front and going faster. Check your understanding 18.3 1 a) y = 3x + 4 b) y= 3x c) y = –4x + 2 gradient 3 gradient 3 gradient –4 intercept 4 intercept 0 intercept 2 intercept 2 a) y = 2x + 4 3 gradient 2 b) y = 14 x – 3 4 gradient 1 4 4 3 intercept – 34 c) y = – 32 × + 6 gradient – 32 intercept 6 3 a) y = –x + 10 gradient –1 intercept 10 3 4 b) y = x + 5 4 c) y = – 43 x + gradient 1 3 3 4 gradient – 43 intercept 5 4 intercept 1 3 Check your understanding 18.4 1 a) Plan B b) Plan B c) 400 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 17 l ANSWERS 19 Bearings and drawings Check your understanding 19.1 Spotlight on the test (page 81) 1 168 cm (1.68 m) 1 11.24 m 2 24 mm 2 b) 8.9 m 3 1 : 50 000 3 10 4 10.5 cm 8 5 250 m V 6 Check your understanding 19.2 4 1 A 074°, B 118°, C 198°, D 249°, E 295°, F 352°. 2 Check your understanding 19.3 1 A 0 B A B 2 4 6 8 10 b) 5 km c) 7.1 km d) 1 : 100 000 Flowerbed Gravel path D C 2 M 18 R Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 ANSWERS l 20 Circles, cylinders and prisms Check your understanding 20.1 Check your understanding 20.3 1 Area 28.3 cm2, circumference 18.8 cm. 1 Area of cross-section = 16 cm2, volume = 160 cm3. 2 Area 78.5 cm2, circumference 31.4 cm. 2 Area of cross-section = 9 cm2, volume = 72 cm3. 3 Area 113 cm2, circumference 37.7 cm. 4 Area 201 cm2, circumference 50.3 cm. 5 Area 154 cm2, circumference 44.0 cm. Spotlight on the test (page 85) 6 Area 38.5 cm2, circumference 22.0 cm. Check your understanding 20.2 1 CSA = 251 cm2, volume = 628 cm3. 2 CSA = 528 cm2, volume = 1850 cm3. 3 CSA = 94.2 cm2, volume = 141 cm3. 1 a) 56.5 cm b) 254 cm2 2 a) 8 cm b) 41.1 cm2 (25.1 + 16) 3 a) 251 cm3 b) 126 cm2 4 a) 24 cm2 b) 96 cm3 4 CSA = 50.3 cm2, volume = 101 cm3. 5 452 cm3. 6 138 cm2. 21 Probability Check your understanding 21.1 1 1 4 2 3 12 3 (= or 0.12) 100 25 4 0.1 5 a) 0.4 b) 0.8 Spotlight on the test (page 88) 2 5 1 a) 2 a) H H 3 a) 8 c) 2 H (H, H) (H, T) T (T, H) (T, T) 1 2 3 4 5 6 1 1 2 3 4 5 6 2 2 4 6 8 10 12 b) 3 3 6 9 12 15 18 1 4 60 = 0.6 100 5 5 10 15 20 25 30 b) 4 4 a) 0.2 5 (= 0.25) 4 4 8 12 16 20 24 b) 2 0.8 Check your understanding 21.2 1 a) 40 = 0.4 100 6 6 12 18 24 30 36 b) 0.65 c) 6 2 1 = 18 9 b) 4 1 = 36 9 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013 19 l ANSWERS 22 Written and mental arithmetic methods Check your understanding 22.1 Spotlight on the test (page 90) 1 6072 2 1062 1 a) 4.5 b) 550 3 4617 4 5632 5 18 872 6 2233 2 70 7 29 172 8 8760 3 101.52 9 50.24 10 60.68 11 178.2 12 43.5 13 1.44 14 0.12 15 163.2 16 14.62 23 Problem solving P1 12 m P8 253 (since 235 is not a multiple of 11) P2 5, 5, 6, 7, 8 P9 31.8 m P3 Snail D (their distances per minute are 48, 45, 42, 51, 36 cm) P10 No: 182 + 302 = 1224 but 352 = 1225 P4 12.6 cm P5 a) 16.6 P6 10 beads b) 6 P11 69, 101 and 1037 P12 a) 6x – 60 = 180 b) 40°, 90°, 50° c) right-angled triangle P7 n = 15 20 Cambridge Checkpoint Mathematics Revision Guide 1 © Hodder & Stoughton Ltd 2013