eShop USA > Books > Fractals, Googols, and Other Mathematical Tales
Fractals, Googols, and Other Mathematical Tales
Availability: Usually ships in 24 hours
List Price: $10.95Our Price: $8.76 You Save: $2.19 (20%)Prices subject to change.
Customer Reviews
Rating:  - Let's clear this up
C=pi*d. That means the diameter has to be **multiplied** by "three and a little bit" in order to be equivalent to, or wrap around, the circumference of the circle. It takes "three and a little bit" diameters to get around the circle one time, not one diameter to get around the circle three and a little bit times. The engineer was right! Other than that, it was still a pretty good book, though. If you're a teacher with an older class, you can see if they can spot the error.
Rating:  - Could I help clarify?
I believe the quote about the circumference and diameter is worded incorrectly. We all know that the size of the diameter and circumference are proportional (hence pi), but the diameter would never wrap around a circumference 3 and a little times! This is obviously false because the circumference is larger than the diameter. The circumference would wrap around the diameter 3 and a little times. Please check your books to determine if the quote is correct in R. Krapf's review - if so, then the book is WRONG!
Rating:  - Revieing the reviewer
I am not sure what R. Krapf "Engineer" (below) was thinking when he/she wrote his/her review...
The circumference of a circle (C) is calculated as 2 * pi * r (or pi * 2 * r)
Since r is the radius and 1/2 the diameter (d), that means C = pi * d
Since pi is about 3.14, that means the book is correct. The diameter of a circle would wrap around (the circumference of) the circle "3 and a little bit"
Rating: - In response to a recent misguided review
Another reviewer reported being dissapointed because the description of pi in the book was "obviously wrong stating that the diameter of a circle would wrap around the circle '3 and a little bit'" and "how can I trust this book knowing that the editors missed such a glaring error?"
It is this reviewer's comment that is 'very confusing' and misleading, not the content of the book.
The definition of Pi is the ratio of the circumference to the diameter of a circle; approximately equal to 3.14159265358979323846... Euclid proved that this ratio (Circumference to diameter aka circumference to twice the radius) is always the same, no matter the size of the circle. What he did was inscribe similar regular polygons in any two circles. Then, he increased the number of sides of the inscribed regular polygons. He reasoned that as the number of sides increased, the perimeter of the inscribed polygon gets closer and closer to the circumference of the circle. He also showed that the perimeters of the similar polygons were proportional to the radii of the circles in which they were inscribed. And so, C is proportional to r, in other words C/r is a constant. By convention, pi=C/2r. (I borrowed these particular words from Jim Loy's website, thanks JL!)
Therefore, the statement the book makes is perfectly, mathematically true (QED!) albeit that it substitutes "a little bit" for 0.14159265358979323846... which I find perfectly acceptable for a children's book, don't you?
p.s. I'm an engineer, too. Cheers!
Rating:  - The Story of Pi
I was disappointed. While skimming through the book prior to giving it to my 7 year old son, I stumbled on the Chapter on "PI". It was obviously wrong stating that the diameter of a circle would wrap around the circle "3 and a little bit". Now, how can I trust this book knowing that the editors missed such a glaring error? Could be very confusing to a young aspiring mathmetician.
Featured Listmania!
| |
 |
