""Mathematical Curiosities takes the reader on a delightful journey through the fascinating relationships that exist in mathematics. From amazing arithmetic surprises to a gaggle of geometry gems, this book will instill a love and appreciation for the beauty of mathematics in both experienced and casual mathematicians. You are sure to enjoy this foray into the curious and surprising mathematical world that, until now, was only accessible to professional mathematicians and enthusiasts.” —Daniel Jaye, chief academic officer, Solomon Schechter Day School of Bergen County “This book truly presents a most unusual collection of mathematical curiosities that will motivate and interest a broad audience. I was amazed at the plethora of clever relationships that have been exposed by the authors—many of which will be new to most readers—despite the fact that most are relatively elementary. This book, which demonstrates many mind-boggling mathematical relationships, should be attractive to those who already love mathematics, and it should win over those who might be skeptical about their relationship with this subject.” —Charlotte K. Frank, PhD, senior advisor, Research and Development, McGraw-Hill Education “It’s a treasure trove, indeed.... There are many reasons to share in this arithmetic potluck with the authors. Did you ever hear anything about the clever way Babylonian peasants solved multiplications of large numbers? This book will tell you and entertain you.” —Dr. Gerhard Ackermann, professor and retired president, Beuth University of Applied Sciences, Berlin “Posamentier and Lehmann are bringing back two neglected arts: the joy of teaching and the joy of learning. Nothing could be more important.” —Harry Phillips III, New York State Board of Regents “