by Deborah Rumsey,PhD Probability FOR DUMmIES ‰ 01_751413 ffirs.qxd 2/24/06 10:29 PM Page iii 01_751413 ffirs.qxd 2/24/06 10:29 PM Page ii Probability FOR DUMmIES ‰ 01_751413 ffirs.qxd 2/24/06 10:29 PM Page i 01_751413 ffirs.qxd 2/24/06 10:29 PM Page ii by Deborah Rumsey,PhD Probability FOR DUMmIES ‰ 01_751413 ffirs.qxd 2/24/06 10:29 PM Page iii Probability For Dummies® Published by Wiley Publishing, Inc. 111 River St. Hoboken, NJ 07030-5774 www.wiley.com Copyright © 2006 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 permit- ted 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: 2005938252 ISBN-13: 978-0-471-75141-0 ISBN-10: 0-471-75141-3 Manufactured in the United States of America 10 9 8 7 6 5 4 3 2 1 1B/RV/QT/QW/IN 01_751413 ffirs.qxd 2/24/06 10:29 PM Page iv About the Author Deborah Rumsey has a PhD in Statistics from The Ohio State University (1993). Upon graduating, she joined the faculty in the Department of Statistics at Kansas State University, where she won the distinguished Presidential Teaching Award and earned tenure and promotion in 1998. In 2000, she returned to Ohio State and is now a Statistics Education Specialist/Auxiliary Faculty Member for the Department of Statistics. Dr. Rumsey has served on the American Statistical Association’s Statistics Education Executive Committee and is the Editor of the Teaching Bits section of the Journal of Statistics Education. She’s the author of the books Statistics For Dummies and Statistics Workbook For Dummies (Wiley). She also has published many papers and given many professional presentations on the subject of Statistics Education. Her particular research interests are curricu- lum materials development, teacher training and support, and immersive learning environments. Her passions, besides teaching, include her family, fishing, bird watching, driving a new Kubota tractor on the family “farm,” and Ohio State Buckeye football (not necessarily in that order). 01_751413 ffirs.qxd 2/24/06 10:29 PM Page v 01_751413 ffirs.qxd 2/24/06 10:29 PM Page vi Dedication To my husband Eric: Thanks for rolling the dice and taking a chance on me. To my son Clint Eric: Your smile always brings me good luck. Author’s Acknowledgments Thanks again to Kathy Cox for believing in me and signing me up to write this book; to Chrissy Guthrie for her continued excellence and for being a won- derful source of support as my project editor; and to Dr. Marjorie Bond, Monmouth College, for another invaluable technical review. Thanks to Josh Dials for his editing that kept things light. Thanks to Kythrie Silva for believ- ing in me; to Peg Steigerwald for her constant support and friendship; and to my family, especially my parents, for loving me through it all. I also wish to thank all the students I have had the privilege of teaching; you are the inspi- ration for all of my work. 01_751413 ffirs.qxd 2/24/06 10:29 PM Page vii 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 Project Editor: Christina Guthrie Acquisitions Editor: Kathy Cox Copy Editor: Josh Dials Editorial Program Coordinator: Hanna K. Scott Technical Editor: Marjorie Bond, PhD Editorial Manager: Christine Meloy Beck Editorial Assistants: Erin Calligan, Nadine Bell, David Lutton Cover Photos: © Medioimages/Getty Images Cartoons: Rich Tennant (www.the5thwave.com) Composition Services Project Coordinator: Adrienne Martinez Layout and Graphics: Andrea Dahl, Carrie A. Foster, Lauren Goddard, Denny Hager, Heather Ryan Proofreaders: Dwight Ramsey, Evelyn W. Still Indexer: Broccoli Information Management Special Help Neil Johnson 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 01_751413 ffirs.qxd 2/24/06 10:29 PM Page viii