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Topic: how many coins?
Replies: 5   Last Post: Apr 8, 1995 3:01 PM

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 Jim Osborn Posts: 3 Registered: 12/6/04
Re: how many coins?
Posted: Apr 7, 1995 12:38 PM

On Fri, 7 Apr 1995, Tad Watanabe wrote:

>
> Does anyone have a proof to the following:
>
> Given a rectangular region of 2cm by 1000cm. You can fit 2011 (I think
> it was 2011. It is more than 2000) coins of 1cm diameter in this region.
>
> On the surface, it appears that the answer should be 2000, but someone at
> the Bell Lab apparently proved that you can fit more (which, by the way,
> is very significant for communication folks since each "coin" can be a
> fiberoptic cable in an underground cable cases).
>
> ************************************************************************

There are three rows of coins instead of two

.. ..
. . . .
. . .. . .
.. . . ..
.. . . ..
. . .. . .
. . . .
.. ..

There are more coins packed into the middle row then are lost by the
missing pairs of coins.

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