01_288177-ffirs.qxp 7/28/08 12:57 PM Page i Basic Math & Pre-Algebra Workbook FOR DUMmIES‰ by Mark Zegarelli 01_288177-ffirs.qxp 7/28/08 12:57 PM Page ii 01_288177-ffirs.qxp 7/28/08 12:57 PM Page i Basic Math & Pre-Algebra Workbook FOR DUMmIES‰ by Mark Zegarelli 01_288177-ffirs.qxp 7/28/08 12:57 PM Page ii Basic Math & Pre-Algebra Workbook For Dummies® Published by Wiley Publishing, Inc. 111 River St. Hoboken, NJ 07030-5774 www.wiley.com Copyright © 2008 by Wiley Publishing, Inc., Indianapolis, Indiana Published by Wiley Publishing, Inc., Indianapolis, Indiana Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400, fax 978-646-8600. 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Library of Congress Control Number: 2008932076 ISBN: 978-0-470-28817-7 Manufactured in the United States of America 10 9 8 7 6 5 4 3 2 1 01_288177-ffirs.qxp 7/28/08 12:57 PM Page iii About the Author Mark Zegarelliis the author of Basic Math & Pre-Algebra For Dummies (Wiley), Calculus II For Dummies (Wiley), Logic For Dummies(Wiley), and numerous books of puzzles. Heholds degrees in both English and math from Rutgers University and lives in Long Branch, New Jersey, and San Francisco, California. 01_288177-ffirs.qxp 7/28/08 12:57 PM Page iv 01_288177-ffirs.qxp 7/28/08 12:57 PM Page v Dedication For my good friend Michael Konopko, with profound admiration, love, and each other’s puzzle pieces. Author’s Acknowledgments I wish to thank once again my acquisitions editor Lindsay Lefevere for all her support and encouragement throughout the writing process. Many thanks to project editor TimGallan for going above and beyond the call of duty many times along the way — Iowe you a deep debt of gratitude for all your help. Thanks to senior copy editor Danielle Voirol for making a ton of valuable suggestions that greatly improved this book.And thanks to technical editor David Herzog for keeping me on the right path. And of course, thank you to my partner Mark Dembrowski, for always being there and calling me to my best. 01_288177-ffirs.qxp 7/28/08 12:57 PM Page vi Publisher’s Acknowledgments We’re proud of this book; please send us your comments through our Dummies online registration form located at www.dummies.com/register/. Some of the people who helped bring this book to market include the following: Acquisitions, Editorial, and Media Development Composition Services Senior Project Editor:TimGallan Project Coordinator: Katherine Key Acquisitions Editor: Lindsay Sandman Lefevere Layout and Graphics:Ana Carrillo, Carrie A. Cesavice, Reuben W. Davis, Senior Copy Editor:Danielle Voirol Nikki Gately, Shane Johnson Editorial Program Coordinator:Erin Calligan Mooney Proofreaders:Laura Albert, Laura L. Bowman Technical Editor: David Herzog Indexer:Ty Koontz Editorial Manager:Michelle Hacker Editorial Assistants:Joe Niesen, Jennette ElNaggar, David Lutton Cartoons: Rich Tennant (www.the5thwave.com) Publishing and Editorial for Consumer Dummies Diane Graves Steele, Vice President and Publisher, Consumer Dummies Joyce Pepple, Acquisitions Director, Consumer Dummies Kristin A. Cocks, Product Development Director, Consumer Dummies Michael Spring, Vice President and Publisher, Travel Kelly Regan,Editorial Director, Travel Publishing for Technology Dummies Andy Cummings,Vice President and Publisher, Dummies Technology/General User Composition Services Gerry Fahey,Vice President of Production Services Debbie Stailey,Director of Composition Services 02_288177-ftoc.qxp 7/28/08 12:57 PM Page vii Contents at a Glance Introduction.............................................................................1 Part I: Back to Basics with Basic Math......................................5 Chapter 1:We’ve Got Your Numbers...................................................................................................7 Chapter 2:Smooth Operators: Working with the Big Four Operations........................................23 Chapter 3:Getting Down with Negative Numbers...........................................................................37 Chapter 4:It’s Just an Expression......................................................................................................49 Chapter 5:Dividing Attention: Divisibility, Factors, and Multiples...............................................69 Part II: Slicing Things Up: Fractions, Decimals, and Percents....89 Chapter 6:Fractions Are a Piece of Cake..........................................................................................91 Chapter 7:Fractions and the Big Four............................................................................................107 Chapter 8:Getting to the Point with Decimals...............................................................................141 Chapter 9:Playing the Percentages.................................................................................................163 Part III: A Giant Step Forward: Intermediate Topics................175 Chapter 10:Seeking a Higher Power through Scientific Notation...............................................177 Chapter 11:Weighty Questions on Weights and Measures..........................................................187 Chapter 12:Shaping Up with Geometry..........................................................................................201 Chapter 13:Getting Graphic: Cartesian Graphs.............................................................................221 Part IV: The X Factor: Introducing Algebra.............................233 Chapter 14:Expressing Yourself with Algebraic Expressions......................................................235 Chapter 15:Finding the Right Balance: Solving Algebraic Equations.........................................255 Part V: The Part of Tens........................................................271 Chapter 16:Ten Alternative Numeral and Number Systems........................................................273 Chapter 17:Ten Curious Types of Numbers..................................................................................281 Index...................................................................................287