Mental Math

305 Pages·2009·1.53 MB·English

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SECRE+S
OF
+ +
MEN AL MA H
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+
SECRE S
OF
+ +
MEN AL MA H
The Mathemagician’s Guide to Lightning Calculation
and Amazing Math Tricks
Arthur Benjamin
andMichael Shermer
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Copyright © 2006 by Arthur Benjamin and Michael Shermer
All rights reserved.
Published in the United States by Three Rivers Press, an imprint of the Crown
Publishing Group, a division of Random House, Inc., New York.
www.crownpublishing.com
Originally published in different form as Mathemagicsby Lowell House,
Los Angeles, in 1993.
Three Rivers Press and the Tugboat design are registered trademarks of Random
House, Inc.
Library of Congress Cataloging-in-Publication Data
Benjamin, Arthur.
Secrets of mental math : the mathemagician’s guide to lightning calculation and
amazing math tricks /Arthur Benjamin and Michael Shermer.—1st ed.
p. cm.
Includes bibliographical references and index.
1. Mental arithmetic—Study and teaching. 2. Magic tricks in mathematics
education. 3. Mental calculators. I. Shermer, Michael. II. Title.
QA111.B44 2006
510—dc22
2005037289
eISBN: 978-0-307-34746-6
v1.0
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I dedicate this book to my wife,Deena,
and daughters,Laurel and Ariel.
—Arthur Benjamin
My dedication is to my wife,Kim,
for being my most trusted confidante
and personal counselor.
—Michael Shermer
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Acknowledgments
The authors wish to thank Steve Ross and Katie McHugh at
Random House for their support of this book. Special thanks to
Natalya St. Clair for typesetting the initial draft, which was
partly supported by a grant from the Mellon Foundation.
Arthur Benjamin especially wants to acknowledge those who
inspired him to become both a mathematician and a magician—
cognitivepsychologistWilliamG.Chase,magiciansPaulGertner
and James Randi, and mathematicians Alan J. Goldman and
Edward R. Scheinerman. Finally, thanks to all of my colleagues
and students at Harvey Mudd College, and to my wife, Deena,
anddaughters,LaurelandAriel,forconstantinspiration.
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