Schoenborn - Math For Real Life For Dummies

Math For Real Life For Dummies

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Copyright 2013 by John Wiley & Sons, Inc., Hoboken, New Jersey

Published by John Wiley & Sons, Inc., Hoboken, New Jersey

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Library of Congress Control Number: 2012955837

ISBN 978-1-118-45330-8 (pbk); ISBN 978-1-118-45332-2 (ebk); ISBN 978-1-118-45334-6 (ebk); ISBN 978-1-118-45331-5 (ebk)

Manufactured in the United States of America

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About the Author

Barry Schoenborn lives in Nevada City, California. Hes a longtime math, science, and technical writer, with over 35 years experience. Hes written hundreds of user manuals. In the past, Barrys tech-nical writing company worked with the State of California agency CalRecycle to teach scientists and administrators how to write clearly.

Barrys the coauthor of Technical Math For Dummies, Medical Dosage Calculations For Dummies, Physician Assistant Exam For Dummies, and Storage Area Networks: Designing and Implementing a Mass Storage System.

He was a movie reviewer for the Los Angeles Herald-Dispatch newspaper and wrote a monthly political newspaper column for The Union newspaper of Grass Valley, California, for seven years. He also writes dental humor, a funny genre that nobody except a dentist would want to read.

Barrys publishing company, Willow Valley Press, published Dandelion Through the Crack, which won the William Saroyan International Prize for Writing.

Dedication

I dedicate this book to Lynda Straus, my long-time intimate friend. She is one of the brightest people I know and is an excellent technical writer. However, she stays very busy, mostly acting as caregiver for her mother and has never made math a focus. Oops! In many ways, she is my model for the ideal reader of this book.

Authors Acknowledgments

I want to thank Lindsay Lefevere, Executive Editor, for the opportunity to write this book. A big thanks, too, to Matt Wagner of Fresh Books Literary Agency, who presented me to Wiley.

Many thanks to the Wiley team: Tracy Barr, Project Editor, and Michael McAsey and Shira Fass, the technical reviewers. They worked very hard to make this book more accurate and easier to read. Without them, there wouldnt be a book.

Publishers Acknowledgments

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Acquisitions, Editorial, and Vertical Websites

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Executive Editor: Lindsay Sandman Lefevere

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Technical Editors: Michael McAsey, Shira Fass

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Cover Photos: PixelEmbargo / iStockphoto.com

Cartoons: Rich Tennant (www.the5thwave.com)

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Introduction

M ath is great. Ive spent my life enjoying math and getting the benefits from it. But many people dont think math is so hot: They have fear and loathing.

The trouble is, a lot of what you learned in school probably was boring or painful, and most likely you forgot it right away. Or you may have deliberately not learned some types of math at all just to save yourself the trouble of forgetting them later. Why? Mainly because a lot of the math taught in schools wasnt math you could use. Well, that nonsense stops here, because this book is filled with math you can use. Heres just a brief sampling of the areas where youll find real-life math to be useful: