Cambridge Lower Secondary Complete Mathematics Second Edition Deborah Barton 8 TEACHER HANDBOOK Sign up to access your Cambridge Lower Secondary Complete Mathematics online Kerboodle course What is Kerboodle? Kerboodle is a digital platform that works alongside your course textbooks to create a truly blended learning solution. Available for purchase by your school as an annual subscription, it can help you to: • Reinforce learning with supportive resources • Track results and progress with quizzes and Markbook • Boost performance with assessment materials • Promote independent learning with online versions of the Student Books • Improve the classroom experience by highlighting, annotating and zooming in on specific features 2 Expressions 2 • • 3 × 5a = 15a (multiply numbers together, then write in front of the letter) 2 p × 3q = 2 × p × 3 × q (multiply numbers first) 2 × 3 × p × q = 6 pq y × y = y 2 ( we say ‘y squared’) p × p × p = p3 ( we say ‘p cubed’) • a÷b= • Expressions • Objectives In this chapter you will learn about zz expressions, including variables and constants z b c a (write as a fraction) b zz expanding brackets zz forming an algebraic expression 2 zz collecting like terms 2 For example: − 2+5= 3 4 + − 7 = 4 − 7 = −3 − 6 − −1 = −6 + 1 = −5 What’s the point? The use of symbols or letters for numbers helps to describe relationships among variables. For example, the speed (v ) of a race car is related to the time (t ) it takes to travel a particular distance (d ) by v =d ÷t. 3 The area of a rectangle is length × width. 4 The perimeter of a shape is the distance around it. Work out: a b c d e f How to add and subtract with negative numbers Simplify: p+ p+ p+ p+ p i ii G + G iii b + b + b − b iv m + m − m − m v p× p vi m × m × m vii t ÷ p 3 x can be written as 3 × x or in full as x + x + x. Write in full: ii 5 y i 4m − 8 + 10 4 − 12 3 + −9 − 3− 4 − 7 − −5 − 1 + −8 3 What is the area of a rectangle of length 12 cm and width 8 cm? 4 Find the perimeter of this shape. 3 cm 2 cm 4 cm 5 cm Before you start You should know ... Check in 1 1 The basics of algebra: • • • • 26 a + a + a = 3 × a or 3a for short. No need for the multiplication symbol when letters are used. This is called simplifying or collecting like terms. a × 5 = 5a (write the number first) a × b = ab for short b × 3 × a = 3ab for short (number first, then letters in alphabetical order) a Write the following in a shorter way. i 4× p ii t × 3 iii h × k iv a × b × c v 2 × 4m vi 7 y × 5 vii a × 2 × b viii 3n × 4u ix 4t × 6r 2.1 Expressions Here is some key language about, for example, 3 x + 7. In maths we try to make things simpler by writing as few words as possible. For example, these two sentences can be written in a shorter way: zz3 x + 7 is an expression, in this case involving 3 apples and 7 bananas = 3a + 7b 6 apples and 12 bananas = 6a + 12b We have used the letter a to represent apples, the letter b to represent bananas and the + symbol to replace the word ‘and’. The process of using letters to represent unknown numbers or variables is algebra. numbers letters and a + symbol. zzA constant is a symbol which always means the same thing, so 7 is a constant. zzA term is part of an expression so 3 x and 7 are the two terms in the expression. 3 x is the algebraic term and 7 is the number term. zzAn unknown is part of an expression that you don’t know the value of, so x is the unknown. zzThe coefficient is the number part of an algebraic term so, in 3x, the 3 is the coefficient. 27 For more information, visit: www.oxfordsecondary.com/cambridge-lowersecondary-maths Need help? Contact your local educational consultant: www.oxfordsecondary.com/contact-us Contents About this book 4 Active learning resources Negative numbers jigsaw 5 Factorizing expressions wheel 11 Mindfulness fractions and decimals puzzle 18 Dining investigation 20 Equations treasure hunt 24 Angle properties pairs game 33 Statistics word search 36 Transformations puzzle 38 Probability collective memory activity 42 Resources for use with Student Book 8 The sieve of Eratosthenes 44 Percentages game 45 Revision material Multi-choice Exercise A 49 Multi-choice Exercise B 54 Multi-choice Exercise C 59 Answers to multi-choice Exercises A, B and C 64 Topic tests Topic test – Chapters 1–5 66 Topic test – Chapters 6–10 74 Topic test – Chapters 11–15 82 Answers to topic tests 93 Progression test-style papers Paper 1 (non-calculator) 97 Mark scheme for Paper 1 105 Paper 2 (calculator) 108 Mark scheme for Paper 2 119 Worked solutions Worked solutions for some of the more difficult questions from Student Book 8 122 Answers Answers for Student Book 8 129 Answers for Homework Book 8 169 Additional support can be found on Kerboodle. As well as extra assessments to accompany the Teacher Handbook, there are resources for each chapter in the Student Book, including interactives and worksheets for both formative and summative assessment. 3 About this book This book is designed to provide teachers with useful resources to support teaching of the Cambridge Secondary Stage 8 Mathematics curriculum framework in preparation for the Cambridge Checkpoint assessments and further study at IGCSE. The active learning resources included ensure that there is plenty of scope for discussion and group work, which are valuable tools for reinforcing learning. Often students complete such activities thinking that they have done very little work as they have written little or nothing down. However, the work completed is often of greater value than a written task, as there is more scope for sharing knowledge and eliminating common misconceptions than when students work individually. There is less pressure than in a written exercise as these resources can have different starting points, meaning students can work in an order that suits them and their level of understanding. Often there are no limits to learning, particularly when using the creative alternative approaches. You will find many students work at higher levels than expected, because of their natural competitiveness and desire to improve. Also, in group work and discussion, students are required to articulate sometimes quite complex mathematical ideas that wouldn’t be covered when working individually. Not everyone learns best by writing things down. These activities address alternative learning styles, particularly if you find your classes often take the ‘teacher gives examples, students do an exercise’ approach. All good resources should provide you with the opportunity to simplify or extend the resource as necessary. Explanations are provided here for how to differentiate the resources to cater for differing ability levels. Sometimes an activity takes less time than 4 About this book anticipated and this can be difficult to manage in lessons, so there are sections suggesting alternative ways to use the resources. There are also resources for exercises in the Student Book that promote active learning; this ensures better understanding, and consequently better retention of the subject knowledge. Revision material is included in the book in the form of multi-choice questions. These can be given to the students as worksheets at the end of a chapter or series of chapters, or they could be used in a more fun approach, for example as a quiz. Assessment materials are provided in the form of topic tests and end-of-year progression tests. The assessment materials are balanced between all the content areas in the framework: number, algebra, geometry and measure, statistics and probability. They are also underpinned by thinking and working mathematically questions, providing a structure for the application of mathematical skills. Mental strategies are tested throughout. Mark schemes are included for all topic tests, and these are provided in great detail for the endof-year progression tests (all mark schemes have been written and developed by the author). There are worked solutions to some of the more difficult questions in the Student Book and answers to all of the exercises in the Student Book and the Homework Book and of course, don’t forget Kerboodle, where you will find yet more resources. Finally, I hope that all the material in this book is extremely useful for you, both in monitoring your students’ progress and helping them increase their understanding and enjoyment of maths. Deborah Barton Active learning resources Mindfulness fractions and decimals puzzle For use with Chapter 6 of Student Book 8 Teacher’s notes Example 6 This mindfulness colouring activity is a fun alternative to a written exercise. This activity requires students to be able to: Work out 6 2 × 4 5 • multiply and divide by 0.1 and 0.01 = 24 + 8 • round to given significant figures = 24 + 1 3 • change a fraction to a recurring decimal = 25 3 • subtract mixed numbers • divide by a proper fraction • multiply by a mixed number. Introductory activity This activity can be used as a plenary or revision exercise supporting the work completed in Chapter 6. You may find that little introduction is necessary. Alternatively, you may want to go through the following examples. Example 1 5 5 5 Mindfulness activity Give each student a copy of the puzzle page. Ask them to colour in all the correct answers to the questions until they find a shape. Differentiation To make it more difficult, students could be asked to write questions that give the ‘solutions’ around the outside edges of cat shape. Alternative approaches 17 × 0.1 = 17 ÷ 10 = 1.7 You could ask students to make an entirely new puzzle of their own. 4.2 ÷ 0.01 = 4.2 × 100 = 420 Answers . 0. 4 0.12 4 0.004 231 to 2 s.f. is 0.0042 4500 0.073 7 9 Example 3 18 39 . 0. 6 0.03 1300 38 45 1000 0.08 25.5 Example 2 30 524 to 2 s.f. is 31 000 5 Change the fraction to a recurring decimal 9 0. 5 5 5… 9 5.505050… . 5 = 0.5 9 Example 4 Work out 4 1 − 1 2 5 3 3 = 4 − 1 10 15 15 18 10 = 3 −1 15 15 8 = 2 15 Example 5 Work out 5 ÷ 2 3 = 5× 3 2 5 = ×3 1 2 = 15 2 = 7 18 5 = 6×4+ 2 ×4 1 2 Active learning resources 17 1 2 3 11 30 Active learning resources Mindfulness fractions and decimals puzzle 300 17.5 13 1 18 0.3 35 2 17 12 0.03 7 9 4.9 18 0.6 5 25 12 0.6 3 67 38 45 0.12 35 45 25. 5 8000 40 0.08 0.07 . 0.3 0 7 3 30 4500 14 29 1000 0.073 1 32 2 45 3 11 30 2.3 7 20 5 0.09 0.13 1200 8 4.5 101 30 999 7 10 2 0.4 0.0 1300 3.25 7.9 4 12 51 2 0.1 130 13 000 3000 30 1 14 14 5 4520 4.4 10 000 80% 1.2 0.085 45 3 0.04 39 1 34 900 1200 Shade in the regions with the answers to these: The fraction 4 as a recurring decimal 9 4524 rounded to 2 s.f. 12 × 0.01 0.4 ÷ 0.1 0.07251 rounded to 2 s.f. . 0. 7 as a fraction its simplest form 8 9 7 ×5 0.3 × 0.1 13 ÷ 0.01 999 rounded to 1 s.f. 0.08499 rounded to 1 s.f. 16 ÷ 7÷ 4 5 2 as a mixed number in its simplest form 5 The fraction 2 as a recurring decimal 3 4 9 2 −1 8×3 5 3 5 3 as a decimal 16 7 1 − 2 as a mixed number in its simplest form 10 3 Mindfulness fractions and decimals puzzle 19 Cambridge Lower Secondary Complete Mathematics Teacher Handbook Second Edition 8 Cambridge Lower Secondary Complete Mathematics embeds an excellent understanding of the Cambridge Lower Secondary Mathematics curriculum. The stretching approach helps learners to develop the skills required to ® progress to Cambridge IGCSE with confidence. ● Fully prepare for exams – comprehensive coverage of the course ● Develop advanced skills – thinking and working mathematically ● Progress to the next stage – differentiated extension material eases the transition to 14–16 study Student Books, Homework Books and Kerboodle online support are also available as part of this series. www.oxfordsecondary.com/cambridge-lowersecondary-maths Empowering every learner to succeed and progress Full Cambridge curriculum coverage Reviewed by subject specialists Stretching extension activities Embedded critical thinking skills Progression to the next educational stage For additional practice can be used flexibly across the whole school and alongside any other maths resources. www.oup.com How to get in touch: web www.oxfordsecondary.co.uk email schools.enquiries.uk@oup.com tel +44 (0)1536 452620 ISBN 978-1-382-01883-8 9 781382 018838