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hmmm.. there are plenty of series which tend towards pi (see Mathworld for most of them), some of which should require only elementary operations, and which, for a given number of terms, can therefore give an approximation to pi.

However, to be certain that we are sufficiently accurate for a particular digit to be correct, requires us to calculate the next term and show that it is small enough. This would mean some pretty hefty calcuations, especially as the simple series converge pretty slowly.

In hexadecimal, there's a great little formula for calcuating the 'n'th digit, but not in decimal as far as I know - but I may be wrong...

There may be some graphical/geometric way of calculating it, perhaps, which requires measurement of an object at a greater and greater scale?

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You can use only paper and pencil. And infinite time. No other material. And you know math as much as an elementary school student. Can you tell me nearly the exact pi number after nearly infinite time?

I kind of did this with my Dad when I was 3.

Pi number is 3.14152429

I did this by rolling tins, plates (but not pie unfortunately)

Also, I'm English.... is elementary school like english primary?

Any way, when I was three I only knew add and divide.

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I kind of did this with my Dad when I was 3.

Pi number is 3.14152429

I did this by rolling tins, plates (but not pie unfortunately)

Also, I'm English.... is elementary school like english primary?

Any way, when I was three I only knew add and divide.

You got pi correct to 4 decimals by measuring rolling plates?

Also, American elementary school is typically grades K-5, which is about ages 5-10.

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I kind of did this with my Dad when I was 3.

Pi number is 3.14152429

I did this by rolling tins, plates (but not pie unfortunately)

Also, I'm English.... is elementary school like english primary?

Any way, when I was three I only knew add and divide.

If your method is perimeter/diameter, then you can't achieve more then 3 decimals, even you have eagle eyes. But if your method is different, please write it. I know a method by using pins. You draw parallel lines on the ground and let a pin to drop on it, then count the ones that touch the lines and not touch the lines. Their proportion gives the pi number. This is a known method, and gives pi excellent. But my rule was using nothing other than a paper and pencil to write on it. I mean you can do only calculations (+-/x). A 12-13 years old child can do it. By the way your pi is wrong after 5. decimal, pi=3.14.59265.

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gng astray the topic,

I recollect the mnemonic to remember the value of pi

"How I wish I could calculate pi"

which is 3.141592

I can't consider a mnemonic for it.

You should simply memorize it.

Yes, I've a method to calculate it without using anything, and with only (+-X) operations (not /) .

But it is very time consuming, thus I don't advice it.

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I can't consider a mnemonic for it.

You should simply memorize it.

Yes, I've a method to calculate it without using anything, and with only (+-X) operations (not /) .

But it is very time consuming, thus I don't advice it.

I remember there being a Monte Carlo method for the calculation of pi, where you randomly drop toothpicks on a grid of parallel lines where the distance between lines is the same as the length of the toothpick. The ratio of twice the number of toothpicks dropped divided by those that fell and intersected a line converges to pi.

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I remember there being a Monte Carlo method for the calculation of pi, where you randomly drop toothpicks on a grid of parallel lines where the distance between lines is the same as the length of the toothpick. The ratio of twice the number of toothpicks dropped divided by those that fell and intersected a line converges to pi.

I mentioned that method above but I wanted you to get pi without using anything other then a paper and a pencil, both are infinite, and you have a lot of time. Dropping the pencil on the paper is a method but I want you to make only calculation (+-x operations). Monte Carlo method is a magic and an easy method. Few people are aware of it, thus I congratulate you. But I am still asking a method with only calculation.

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