Pi: A Biography of the World's Most Mysterious Number

We all learned that the ratio of the circumference of a circle to its diameter is called pi and that the value of this algebraic symbol is roughly 3.14. What we weren't told, though, is that behind this seemingly mundane fact is a world of mystery, which has fascinated mathematicians from ancient times to the present. Simply put, pi is weird. Mathematicians call it a "transcendental number" because its value cannot be calculated by any combination of addition, subtraction, multiplication, division, and square root extraction. In this delightful layperson's introduction to one of math's most interesting phenomena, Drs. Posamentier and Lehmann review pi's history from prebiblical times to the 21st century, the many amusing and mind-boggling ways of estimating pi over the centuries, quirky examples of obsessing about pi (including an attempt to legislate its exact value), and useful applications of pi in everyday life, including statistics.This enlightening and stimulating approach to mathematics will entertain lay readers while improving their mathematical literacy.

Alfred S. Posamentier is an American educator and a lead commentator on American math and science education, regularly contributing to The New York Times and other news publications. He has created original math and science curricula, emphasized the need for increased math and science funding, promulgated criteria by which to select math and science educators, advocated the importance of involving parents in K-12 math and science education, and provided myriad curricular solutions for teaching critical thinking in math.

Dr. Posamentier was a member of the New York State Education Commissioner's Blue Ribbon Panel on the Math-A Regents Exams. He served on the Commissioner's Mathematics Standards Committee, which redefined the Standards for New York State. And he served on the New York City schools’ Chancellor's Math Advisory Panel.

Posamentier earned a Ph.D. in mathematics education from Fordham University (1973), a master's degree in mathematics education from the City College of the City University of New York (1966) and an A.B. degree in mathematics from Hunter College of the City University of New York.

Ingmar Lehmann is retired from the mathematics faculty at Humboldt University in Berlin. For many years, he led the Berlin Mathematics Student Society for gifted secondary school students, an organization with which he is still closely engaged today.

He is the author of numerous mathematics texts in Germany and the coauthor with Alfred S. Posamentier of some other books, including The Secrets of Triangles, The Glorious Golden Ratio, Magnificent Mistakes in Mathematics, and The Fabulous Fibonacci Numbers.