"Jack Tingle" <wjtingle@[EMAIL PROTECTED]
> wrote in message
news:MtqdnazG5_AMSEbanZ2dnUVZ_u6rnZ2d@[EMAIL PROTECTED]
> Yesterday being pi-day (3/14 at approximately 1:59:27), I tried a little
> exercise. The most commonly used approximations for this nasty little
> number are 3.1416, 22/7, and 355/113. Since pi is 3.14159... 3.1416 is a
> pretty good approximation, and only requires you to remember five
digits.
> 22/7 only needs 3 digits, while 355/113 needs a prodigious act of memory
> on SIX whole digits [shocked muttering from audience].
>
> Their relative merits, taking 3.14l6 as the baseline, has 22/7 with 172x
> the error of our baseline. Amazingly, hexadigital 355/113 has only 3.6%
of
> the error of the best 5 digit champion, 3.1416! In between, there is
very
> little to challenge this. 311/99 only requires you to memorize five
> digits, but has 24x the baseline error, so it's by far second best to
just
> remembering the number itself.
>
> All in all, 355/113 seems a miracle of parsimony. For the cost of
> memorizing one more digit, you get a gigantic jump in accuracy.
>
> Happy Pi Day*
> Jack Tingle
>
> That's US civil Pi Day. European civil and US military Pi Day is 31
April.
> ;)
I've never had much trouble memorizing 3.141592653589... I can remember
being taught the 22/7 approximation in school around age 10 or 11.
There's a mnemonic poem (in French, maybe an English one also) in which
the
word lengths are successive digits of pi. Can't remember it now (so what
sort of great mnemonic is this?) but I'm hoping someone will chime in
about
here.
ObSFRef: Pi plays a highly significant part in "Contact" by Carl Sagan.
--
Mike Dworetsky
(Remove pants sp*mbl*ck to reply)
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