Remembering PiDate: 08/27/2001 at 22:34:12 From: Paul Subject: An easy way of getting to Pi I would like to find out two things: 1) Is there an easy way of finding Pi, only to 3.141592654, that is memorizable and not too confusing? I memorized 3.14 a long time ago, but for when I am not using a scientific calculator, is there an easy way to get i? I already know 22/7, but that is off by 0.00126. 2) Why did I learn in fifth grade that pi was 3.14285714? Thank you for your time and effort! Date: 08/28/2001 at 09:26:40 From: Doctor Peterson Subject: Re: An easy way of getting to Pi Hi, Paul. Ten digits are perfectly possible to memorize; people have gone a lot farther. I myself use 3.14159, which is more than enough for most purposes. 3.14285714 is 22/7 to eight decimal places; you must have thought that was actually equal to pi. Just unlearn what you learned in fifth grade and replace it with the right value. Another well-known approximation, which is quite easy to memorize, is 355/113; this equals 3.14159292... and is as good as the decimal I use. Note that the odd numbers 1, 3, and 5 appear twice each, in a simple pattern: 113,355, denominator first. Nothing could be much easier than that! - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/ |
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