how did someone come up with pi and why does pi = the circumfrence of a circle

pi does not equal the circumference of a circle. pi is the ratio of the diameter of the circle to the circumference. A lot of information on pi can be found here

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thanx dude it just that i got to thinking about it and i remember that in school they told us how to use it but not why nobody ever called it a ratio
makes a lot of sense when u call it a ratio

What is a balanced diet?
A pie in each hand...

but then if I were to loose the e it becomes pi. The number of times the diameter of a circle goes into the circumference. That being about 3.14 times. Yes the term ratio does make it sensible. I think you can thank the Greek empire for pi. No they did not invent the wheel. They did the maths...

No one "came up with" pi. Pi simply is, and has been since the origen of the universe.

Also, pi does not equal the circumference of a circle. Rather, it equals the circumference divided by the diameter.

As for the history of human involvement with pi, Archimedes was the first person to examine pi extensively. He was quickly followed by others, including Liu Hui (265 AD), Zu Chongzhi (480 AD), Madhave (1400), alKashi (1424), van Ceulen (~1600), Gregory and Leibniz (1600s).

It wasn't until 1706, however, that John Machin became the first person to compute 100 decimals of pi.

Using advanced mathmatics (various series algorithms) and the power of computers (1 TB RAM at 2 TOps (trillion operations per second)) in 2002, the current record was set. It calculated pi to 1.241 Trillion decimals.

Another approach calculated the quadrillionth bit of pi; however, it didn't calculate the ones between the current record and that bit.

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Perception isn't reality. It's merely an abstraction thereof, and quite often not a very good one at that.

I am human. Fully human.

Just because this is BAUT, and I like talking to Tensor: pi is the ratio of the circumference of the circle to the diameter. That other number is also famous, for having "67" appear twice in the first twenty-five digits, but no "2" and no "4".

Yeah, its easy to reverse it when you post too late. I've got to remember not to post when I'm tired. At least I got the link right.

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Some try to tell me, thoughts they cannot defend,... - Moody Blues.

0.0101000101111100110000011+

Or... ones and zeros far as I can see.

On-line Encyclopedia of Integer Sequences: A127266, Expansion of 1/Pi in base 2

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0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0....

As soon as I see the word 'Base' That seems to indicate a dramatic change in the expression of numbers... ie., I am happy with the metric system. After that last post... the blinds have come down, the light turned off. My head hurts...Oh my.

There's also radians.

A measure of angle where instead of 360 degrees in a circle there are 2pi radians in a circle.

Memory of this may have contributed to the OP question.

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Hi PzkpFw!

Pi is a constant ,22/7 or or 3.142..

a bit like the golden ratio(Phi)

Paul

Paul, did you read the thread?

(In any case, neither of your numbers are accurate, nor do they answer the OP.)

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I quickly scanned the other posts, and I saw that many of you stated that pi is a ratio of circumference to diameter, that of course is true, but it also gives the area of a circle in pi x r^2 = A

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~~~ Richard Feynman ~~~

This has already been pointed out, but pi is not 22/7. 22/7 is a rough approximation of pi, "good enough for rock 'n roll" as we sometimes say. But it is not the same. Pi never comes to a repeating pattern, but 22/7 does. Pi is "irrational". Phi is also irrational, so it can't be expressed as a ratio of two integers.

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That must have been time consuming. When I get my first time machine I want to print the first billion digits of pi (I guess about 30 to 40 cases of paper) and leave them stacked in his living room during the night after he finished his hand computation.

I'm sure I read in a local paper (a few years ago) of a man who for a hobby was hand-calculating pi.

Don't know the method.

It was once pointed out to him he had a mistake in about the 50th page (of 70 or so), and he took it pretty much as "oh well".


(I forget the details, sorry, it was a while ago that I read this.)

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some people can calculate PI in their head...mental calculators..000's of places..and they get it right...they don't think about it logically.In comes to them in some other way..I thinks it's a strange gift!

You might be thinking of Daniel Tammet, author of "Born on a Blue Day: Inside the Extraordinary Mind of an Autistic Savant." Tammet has recited the value of Pi without error to the 22,514th degree. He tends to see consistent shapes and colors representing numbers. He also learned to converse in Icelandic in a week. From his book it appears that he tends to think in terms of analogy as well as literally. Tammet has synesthesia and autism but has manged to also develop excellent communication skills, which is very rare.

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How to calculate pi...
It's an infinite series
pi = 4*(1 - 1/3 + 1/5 - 1/7 + 1/9 - 1/11 ....)
If you want to do the maths yourself.

The real reason computers are forced to calculate pi is not that we need to know pi to a gazillion places but that it is a realistic comparison in the computing speeds of various machines.

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I thought it was because there were sadistic programmers.

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masochistic