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Topic: Great Math Tricks on youtube
Replies: 8   Last Post: Jan 1, 2014 9:36 AM

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 Thomas Nordhaus Posts: 433 Registered: 12/13/04
Re: Great Math Tricks on youtube
Posted: Jan 1, 2014 9:36 AM

Am 01.01.2014 01:31, schrieb Christopher J. Henrich:
>

>> On Monday, December 30, 2013 8:37:29 AM UTC, Phil Carmody wrote:
>>> Today I learnt that
>>>
>>> 11.5 / 2 = 6.725
>>>
>>> Teach me more of these internet things called "math tricks"!

>>
>>
>> Apart from that, he tells us that to solve (1 + p / 100)^n = 2 for n we let n
>> = 72 / p,

> A better approximation is 69/p, based on ln(2) = 0.693...

Of course this is a better approximation for very small values of p, but
they are not of very high interest for an investor ;) For values of p
between let's say p=5% and p=20% the 72-rule seems to work better.

--
Thomas Nordhaus

Date Subject Author
12/21/13 Sumit Garg
12/27/13 Wizard
12/30/13 Phil Carmody
12/30/13 Wizard-Of-Oz
12/30/13 Wizard-Of-Oz
12/31/13 Christopher J. Henrich
12/31/13 gnasher729
12/31/13 Christopher J. Henrich
1/1/14 Thomas Nordhaus