Years 6–8 Maths for Students
Published by
Wiley Publishing Australia Pty Ltd
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Milton, Qld 4064www.dummies.com
Copyright © 2016 Wiley Publishing Australia Pty Ltd
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National Library of Australia
Cataloguing-in-Publication data:
| Author: | Colin Beveridge |
| Contributors: | Mark Zegarelli, Ingrid Kemp |
| Title: | Years 6–8 Maths for Students |
| ISBN: | 9780730326731 (pbk.) 9780730326809 (ebook) |
| Series: | For Dummies |
| Notes: | Includes index. |
| Subjects: | Mathematics — Textbooks Mathematics — Study and teaching (Secondary) Mathematics — Problems, exercises, etc. |
| Dewey Number: | 510.76 |
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Introduction
Part I: Whole Numbers: The Building Blocks of Maths
Chapter 1: Ready, Set … Success!
Chapter 2: Getting Bigger and Smaller: Sequences, Addition and Subtraction
Chapter 3: Equal Piles: Multiplying and Dividing
Chapter 4: Going Backwards with Negative Numbers
Chapter 5: Say What? Turning Words into Numbers
Part II: Parts of the Whole
Chapter 6: Cake or Death: Fractions without Fear
Chapter 7: What’s the Point? Dealing with Decimals
Chapter 8: It’s All Relative: Ratios, Proportions and Speed
Chapter 9: Perfect Percentages, 100% of the Time
Chapter 10: Word Problems with Fractions, Decimals and Percentages
Part III: Picturing and Measuring: Shapes, Weights and Graphs
Chapter 11: Shaping Up
Chapter 12: Considering Time, Weights, Temperature and Measurements
Chapter 13: Communicating Data with Graphs and Tables
Part IV: The x-Files: Introduction to Algebra
Chapter 14: Using the Alphabet for Maths
Chapter 15: Using Algebra to Solve Equations
Chapter 16: Algebra Word Problems
Part V: The Part of Tens
Chapter 17: Ten Tricks for Remembering Your Number Facts
Chapter 18: Ten (Almost!) Pitfalls to Avoid
Chapter 19: Ten (or so) Ways to Make Any Test Easier
Index
Once upon a time, you loved numbers. This isn’t the first line of a fairy tale. Once upon a time, you really did love numbers. Remember?
Maybe you were three years old and your grandparents were visiting. You sat next to them on the couch and recited the numbers from 1 to 10. Grandma and Grandpa were proud of you and — be honest — you were proud of yourself, too. Or maybe you were five and discovering how to write numbers, trying hard not to print your 2 and 7 backward.
Learning was fun. Numbers were fun. So what happened? Maybe the trouble started with long division. Or sorting out how to change fractions to decimals. Could it have been figuring out how to take away a 25 per cent discount from the cost of a purchase? Reading a graph? Converting miles to kilometres? Trying to find that most dreaded value of x? Wherever it started, you began to suspect that maths didn’t like you — and you didn’t like maths very much, either.
Why do people often enter kindergarten excited about learning how to count and, somewhere along the line, become convinced that they can’t do maths? The answer to this question would probably take 20 books this size, but solving the problem can begin right here.
I ask you to put aside any doubts. Remember, just for a moment, an innocent time — a time before maths inspired panic attacks or, at best, induced irresistible drowsiness. In this book, I take you from an understanding of the basics to the place where you’re ready to enter any mathematics class and succeed.
Along the road from counting to algebra, most people experience the Great Maths Breakdown. This feels something like when your car begins smoking and sputtering on a 43°C highway somewhere between Noplace and Not Much Else.
Please consider this book your personal roadside helper, and think of me as your friendly maths mechanic (only much cheaper!). Stranded on the freeway, you may feel frustrated by circumstances and betrayed by your vehicle, but for the person holding the toolbox, it’s all in a day’s work. The tools for fixing the problem are in this book.
Not only does this book help you with the basics of math, but it also helps you get past any aversion you may feel toward maths in general. I’ve broken down the concepts into easy-to-understand sections. And because Years 6–8 Maths for Students is a reference book, you don’t have to read the chapters or sections in order — you can look over only what you need. So feel free to jump around. Whenever I cover a topic that requires information from earlier in the book, I refer you to that section or chapter, in case you want to refresh yourself on the basics.
Here are two pieces of advice I give all the time — remember them as you work your way through the concepts in this book:
Although every author secretly (or not-so-secretly) believes that each word she pens is pure gold, you don’t have to read every word in this book unless you really want to. Feel free to skip over sidebars (those shaded grey boxes) where I go off on a tangent — unless you find tangents interesting, of course.
Making assumptions is always a risky business, but knowing where I’m coming from may put you at ease. So, in writing this book, I assume that:
Throughout the book, I use three icons to highlight what’s hot and what’s not:
This icon points out key ideas that you need to know. Make sure you understand before reading on! Remember this info even after you close the book.
Theories are fine, but anything marked with a Tip icon in this book tells you something practical to help you get to the right answer. These are the tricks of the mathematical trade.
The Warning icon highlights errors and mistakes that can cost you marks or your sanity, or both.
This book is set up so you can jump right into the topics that interest you. If you feel like an absolute beginner in maths, I recommend you read Parts I and II to build a foundation for the other topics. If you’re pretty comfortable with the mechanics of maths, use the table of contents and index to find the subject you have questions about right now. This book is a reference — keep it with your maths kit and turn to it whenever you have a question about maths.
Part I
In this part …
Set yourself up for maths success — and understand what maths you’re already good at.
Work with number sequences, addition and subtraction.
Multiply with style and divide with ease.
Get your head around negative numbers.
Understand how to solve word problems — and why doing so can be useful.