How was pi discovered?

Answerd by Kermit Rose

Nobody knows how pi was discovered. We do know that pi has

been known for over 4000 years.

In 2000 BC the Babylonians used 3 1/4 as an approximation to

pi, and the Egyptians used 256/81.

It is very likely that people of thousands of years ago

observed that circles of different sizes were similar. If

you measure the circumference of any circle and divide it by

the diameter of the same circle, you will get the number pi.

It is very easy to think that mathematicians of thousands of

years ago would have noticed that circumference divided by

diameter would always give the same number, regardless of the

size of the circle.

In this sense we may say that pi was discovered by simply

seeing that all circles were similar. Suppose you have two

circles, the first a small circle, and the second a bigger

circle. Then if you have a way to make the smaller

circle bigger, you can turn it into exactly the bigger

circle.

But once it was noticed that pi existed, how was it

calculated?

How did the ancients know how big pi was?

We think that they simply measured large circles. That is

why in ancient times the most frequently approximations of pi

have been 3, or 22/7 or 13/4.

None of these of course are exactly pi. Pi cannot be written

exactly except by naming it. When we write the name pi, we

are specifying exactly the value of pi. When we write 3.14

we are specifying only an approximation to pi.

Back to previous Menu.

Go to Top

Main Menu