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Why Pi?
Focusing on how people from ancient Egyptians to modern scientists have used numbers to measure things through the ages, "Why Pi?" makes math interesting and is filled with games, puzzles, brainteasers, and fun facts. Full color.
96 pages, Hardcover
First published January 1, 2009
6 people are currently reading
87 people want to read
About the author
Johnny Ball
26 books14 followersJohnny Ball is the host of Think of a Number, Think Again (BBC), and Johnny Ball Reveals All (ITV). His shows and videos have won 12 awards, including a New York International Emmy nomination, the ITV "Presenter of the Year" Craft Award, and a BAFTA.
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Displaying 1 - 12 of 12 reviews
May 6, 2012
Katie Young
Picture Book
This book makes you think about numbers by focusing on how numbers are used to measure things now and how they were used to measure things through the ages. This book is broken up into three major sections. The first section, The Ancient World focuses on ancient civilizations and how they discovered measurements by observing things like the moon and sun for night and day, seasons, and months. Next is the Age of Discovery which talks about specific scientists like Copernicus and Galileo and reviews their contributions to math and science. The final section is The Modern Measuring which touches on the development and use of all modern day conveniences like electricity, sound, light, and pressure.
This is a great book for young and old alike. The pictures are great with bright, vivid colors to bring math to life. The language is easy to follow and there is not a lot to read per page. This book is fun and brings math and science to life. It is recommended to any young adults who need a refresher on the basics.
Picture Book
This book makes you think about numbers by focusing on how numbers are used to measure things now and how they were used to measure things through the ages. This book is broken up into three major sections. The first section, The Ancient World focuses on ancient civilizations and how they discovered measurements by observing things like the moon and sun for night and day, seasons, and months. Next is the Age of Discovery which talks about specific scientists like Copernicus and Galileo and reviews their contributions to math and science. The final section is The Modern Measuring which touches on the development and use of all modern day conveniences like electricity, sound, light, and pressure.
This is a great book for young and old alike. The pictures are great with bright, vivid colors to bring math to life. The language is easy to follow and there is not a lot to read per page. This book is fun and brings math and science to life. It is recommended to any young adults who need a refresher on the basics.
February 11, 2010
Aimed at kids 9-12 years old, I found this to be a great read for all ages. I had this book as bathroom reading material, which I found to be the perfect way to read the book. In this way, you could read just a page or two at a time, and then have plenty of time between readings to really think about what you had learned. The beginning of the book was excellent - talked about really interesting math history, such as how Egyptians used math to measure their fields, and who came up with different basic mathematical principles, and how they affect us, etc. The last 1/4 or so of the book was anti-climatic - it was just a discussion of the various different measurements out in the world today. If you skip the last 1/4, you won't miss much. The rest of it though is a great read for young and old alike.
December 2, 2017
In the classroom, we have to solve complicated and boring math problems. However, Johnny Ball takes us away from math class and helps us to understand why math is important in our everyday lives. He tells us the story of math in a fun and interesting way. Who knew that pi is so important and math is not just about memorizing long formulas?
January 25, 2024
The concept of this book is to convey the important fact that numbers are not just for counting things, measuring quantities, or pointing out sizes and distances, but that everything in this world is made up of “Numbers”.
Author Johnny Ball emphasizes that numbers have influenced all kinds of professionals, including explorers, engineers, and scientists, and have evolved in fields as diverse as science, medicine, and architecture.
I empathize with this message 100%.
I believe that the Parthenon in Greece and the Colosseum in Ancient Rome, Italy, were also built by humans at the time using Pi.
However, there was something about the construction of the Egyptian pyramids at the beginning of this book (starting from page 15) that I couldn't understand the explanation in the book.
▼Facts (excerpt from the book)
・The Great Pyramid of Khufu, built in 2560 BC, was the world's tallest building for 4000 years.
・The most important angle for the Egyptians was the right angle, 90 degrees (one quarter of the circumference)
・The corners had to be at right angles so that the blocks could be neatly stacked.
・The angle of inclination remains constant at 52 degrees.
・All the blocks were cut by hand.
・As the height increased by 28 finger widths, the stone was placed 22 finger widths closer to the center.
・The architects checked each corner with a mason's tool called a square lumber.
・The Great Pyramid is made of 2.3 million limestone blocks, some weighing as much as 16.5 tons (15 metric tons).
・The blocks fit together so neatly that you can't squeeze a credit card between them.
▼It is thought that the pyramids were not built by ancient people.
When viewed from space using an artificial satellite, the pyramids line up exactly with the points on the compass in the north.
How did the pyramids, built thousands of years before the invention of the magnetic compass, accomplish this amazing feat?
It is explained that the Egyptians were able to determine the location of east and west by drawing a line perpendicular to the north-south line, but why can't modern humans reproduce what humans were able to do 4,600 years ago?
Around 4,600 years ago, when the pyramids were built, ancient people didn't yet know how to measure distance in meters or miles, so they roughly calculated how long it would take to walk.
For example, they calculated that it would take two days to walk to a distant river or mountain, and roughly estimated the remaining daylight hours by the length of the sun's shadow.
Isn't it hard to believe that with such primitive numerical knowledge alone, the priests of Karnak in southern Egypt had a wonderful temple built in honor of the sun?
It is said that the talented Egyptians calculated the date by tracking the position of the sun's rise, and mathematicians who could do this became priests.
However, it is hard to believe that the people who actually built the pyramids were said to be slaves, and then the architects, and historians' stories keep changing.
It is completely unreasonable that the heavy blocks of stone were said to have been carried on rafts down the Nile by slaves, then dragged up on specially constructed stone slopes on sledges.
Author Johnny Ball emphasizes that numbers have influenced all kinds of professionals, including explorers, engineers, and scientists, and have evolved in fields as diverse as science, medicine, and architecture.
I empathize with this message 100%.
I believe that the Parthenon in Greece and the Colosseum in Ancient Rome, Italy, were also built by humans at the time using Pi.
However, there was something about the construction of the Egyptian pyramids at the beginning of this book (starting from page 15) that I couldn't understand the explanation in the book.
▼Facts (excerpt from the book)
・The Great Pyramid of Khufu, built in 2560 BC, was the world's tallest building for 4000 years.
・The most important angle for the Egyptians was the right angle, 90 degrees (one quarter of the circumference)
・The corners had to be at right angles so that the blocks could be neatly stacked.
・The angle of inclination remains constant at 52 degrees.
・All the blocks were cut by hand.
・As the height increased by 28 finger widths, the stone was placed 22 finger widths closer to the center.
・The architects checked each corner with a mason's tool called a square lumber.
・The Great Pyramid is made of 2.3 million limestone blocks, some weighing as much as 16.5 tons (15 metric tons).
・The blocks fit together so neatly that you can't squeeze a credit card between them.
▼It is thought that the pyramids were not built by ancient people.
When viewed from space using an artificial satellite, the pyramids line up exactly with the points on the compass in the north.
How did the pyramids, built thousands of years before the invention of the magnetic compass, accomplish this amazing feat?
It is explained that the Egyptians were able to determine the location of east and west by drawing a line perpendicular to the north-south line, but why can't modern humans reproduce what humans were able to do 4,600 years ago?
Around 4,600 years ago, when the pyramids were built, ancient people didn't yet know how to measure distance in meters or miles, so they roughly calculated how long it would take to walk.
For example, they calculated that it would take two days to walk to a distant river or mountain, and roughly estimated the remaining daylight hours by the length of the sun's shadow.
Isn't it hard to believe that with such primitive numerical knowledge alone, the priests of Karnak in southern Egypt had a wonderful temple built in honor of the sun?
It is said that the talented Egyptians calculated the date by tracking the position of the sun's rise, and mathematicians who could do this became priests.
However, it is hard to believe that the people who actually built the pyramids were said to be slaves, and then the architects, and historians' stories keep changing.
It is completely unreasonable that the heavy blocks of stone were said to have been carried on rafts down the Nile by slaves, then dragged up on specially constructed stone slopes on sledges.
This entire review has been hidden because of spoilers.
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August 19, 2023This book was good it had a lot of facts but it was kind of boring. I liked all the stuff about how they used to measure things whenever it was in the olden times.
November 2, 2011
Why Pi is a non fiction book about math and how math helps us in everyday life.There's all sorts of interesting facts about the days, months and years, about how the planets and stars move and how the egyptians used math and about how the most famous math geniuses figured out their famouse ideas.This book is really, really interesting.
I picked this book up because I needed a non fiction book for my goodread bookshelves.
I finished this book because it had interesting facts about math.
I would recommend this book to Patrick because he loves cramming his head with math facts and useless pieces of information and this book was full of facts and useless pieces of in formation.
I picked this book up because I needed a non fiction book for my goodread bookshelves.
I finished this book because it had interesting facts about math.
I would recommend this book to Patrick because he loves cramming his head with math facts and useless pieces of information and this book was full of facts and useless pieces of in formation.
March 27, 2014
This is a great book for young and old adults. I really think it is very informative. The pictures are great with bright, vivid colors to bring math to life. The language is easy to follow and there is not a lot to read per page. This book is fun and brings math and science to life. This book makes you think about numbers by focusing on how numbers are used to measure things now and how they were used to measure things through the ages. When I read it I thought that none in my class would read it because it is kind of long, but as second thought I think that this would be great help for those students who love to learn new things everyday.
March 21, 2014
This is actually a really cool book. It tells about the history of how we started measuring all kinds of things--time, angles, years, area, you name it! It would probably good for older elementary children or even middle school kids. I found it very informative and interesting. They also have fun things like speech bubble above the people to spice the book up and make it more interesting. This book would definitely make me enjoy math more!!!
June 4, 2015
Fascinating book about how math is used in real life, starting from ancient times (e.g. using angles to figure out how to measure latitude) up to modern times (e.g. measuring electricity). Lots of interesting and obscure facts, and some actual problems sprinkled in throughout the book. Full color pictures and diagrams keep it engaging for visual learners.
December 30, 2012
Going to use this excellent book as a model for my student projects on Pythagorean theorem and irrational number projects.
Reminds me of the hundreds of DK books I've read in science....but it's all about Pi. Super engaging for a math book.
Reminds me of the hundreds of DK books I've read in science....but it's all about Pi. Super engaging for a math book.
December 2, 2014
This was really good! I liked reading it. It is full of so many facts and why math is the way it is, how the ancient minds found what they did, and how it is practical today. This seems more like an older elementary school book, or a college student who needs a refresher of math facts and why.
April 3, 2014
This book really did make my life and to show me that math is everywhere I am and how to apply that to my life. I think this book would be to teach why we need math.
Displaying 1 - 12 of 12 reviews