HDTenEightyP/NetNews huggingface dataset:
From: cjdcosta@eos.ncsu.edu (CHRISTOPHER J DCOSTA)
Subject: Re: simple puzzle
Originator: cjdcosta@zepplin.ece.ncsu.edu
Reply-To: cjdcosta@eos.ncsu.edu (CHRISTOPHER J DCOSTA)
Organization: North Carolina State University, Project Eos
Date: Thu, 10 Sep 1992 03:49:37 GMT


ta-vg11@muddnext28.cc.columbia.edu (Vikas Gupta) quizzes:
>You have a set of 12 coins .One of them is either heavier or lighter.
>All the rest are of the same weight.You also have a weighing balance.
>What is the minimum number of weighings required to find out the odd coin  
>and also to find the nature of its oddity(i.e. heavier or lighter).
>Also what is the procedure for the same.


1. First balance 6 vs 6.
   Choose the heavier group.

2. Of these 6, balance 3 vs. 3.

   Either of the following is possible, depending on your luck:

         (a)            OR                 (b) 

   They balance out              One side is heavier.
   => The anomalous              => The anomalous coin is 
   coin is lighter               heavier and you have 
   and in the other six          narrowed your search to           
                                 three. 
3. balance three against
   three and isolate the      3. From the final three,
   lighter three, so you're      place any two coins on 
   down to your final three      two pans of the scale
                                  if they balance, then the
4. place any two coins           third coin is anomalous and
   on the two pans of the        heavier otherwise the 
   scale, if they balance        heavier of the two is the
   then the third coin is        odd coin out.
   anomalous and lighter,
   otherwise the lighter         (Three weighings required)
   of the two is the
   anomalous coin.
  
   (Four weighings required)

So the minimum number of weighings within which the odd coin &
the nature of it's oddity CAN be found is THREE, PROVIDED you're
lucky. Otherwise, you'll need FOUR tries.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|   Christopher J. D'Costa           cjdcosta@eos.ncsu.edu |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From: srw@horus.ps.uci.edu (Steven White)
Subject: Re: simple puzzle
Newsgroups: rec.org.mensa
Reply-To: srw@horus.ps.uci.edu (Steven White)
Organization: University of California, Irvine
Date: 10 Sep 92 21:16:54 GMT

In article <1992Sep9.211624.8248@news.columbia.edu>, ta-vg11@muddnext28.cc.columbia.edu (Vikas Gupta) writes:
|> 
|> You have a set of 12 coins .One of them is either heavier or lighter.
|> All the rest are of the same weight.You also have a weighing balance.
|> What is the minimum number of weighings required to find out the odd coin  
|> and also to find the nature of its oddity(i.e. heavier or lighter).
|> Also what is the procedure for the same.
|> 
|> HAve fun
|> Vikas

Lemma 1: Given 3 coins and 1 try, plus knowledge of whether it is
heavier or lighter, it is possible to determine the odd one plus its 
oddity.

Proof: Weigh two of them against each other.

Lemma 2: Given 4 coins and two tries, plus three known-to-be normal
coins, it is possible to determine the odd one plus its oddity.

Proof: Start by weighing 3 of the 4 versus 3 normals.

Main problem: First weigh 4 vs 4. If the scales balance, proof done
by Lemma 2. Otherwise, label the 8 coins weighed as 4 lefts and 4 rights.
Then weigh (1 left + 3 rights) versus (1 right + 3 normals). Then
if is balances, or if it switches from the first weighing, proof done
by Lemma 1. If it balance the same as the first time, then one more
weighing will also do it.

Three tries.

					Steve White

From: Dave.Aronson@p11.f120.n109.z1.fidonet.org (Dave Aronson)
Sender: Uucp@blkcat.UUCP
Newsgroups: rec.org.mensa
Subject: simple puzzle
Date: Thu, 10 Sep 1992 10:38:48 -0500

cjdcosta@eos.ncsu.edu (CHRISTOPHER J DCOSTA) writes:

 CJD> You have 27 coins, one of which is HEAVIER than the rest. 
 CJD> Once again, find the minimum number of trials with a 
 CJD> weighing balance that you'd need to single this coin out.

Much simpler.

1)  Weigh 1 to 9 versus 10 to 18.  If they balance then proceed with 19 to 27
else proceed with the heavier of these groups.

2)  Of the ones you have now, weigh 1 to 3 versus 4 to 6.  If they balance then
proceed with 7 thru 9 else proceed with the heavier of these groups.

3)  Of the ones you have now, weigh 1 versus 2.  If they balance the odd one is
3, else it's the heavier of the above two.
From: dens@flammulated.owlnet.rice.edu (Dennis Allen Schmitz)
Newsgroups: rec.org.mensa
Subject: Re: The nerd stereotype
Date: 7 Sep 92 23:53:59 GMT
Organization: Rice University, Houston, Texas

In article <gTsFqB7w165w@iowegia.uucp> quest@iowegia.uucp (Steve J. Quest) writes:
	   Know that you are NOT alone.  I have found that hot love 
   always grows very cold.  I have also seen with other people that 
   cold love often grows warm.  Being an intense person, I am doomed 
   to the cycle that you and I both find discouraging..........sq

Without intensity, life would pretty damned boring, I think. I seek
out intensity whenever I get the chance.

Later,
den
Newsgroups: rec.org.mensa
From: smaurer@artin.helios.nd.edu (sean maurer)
Subject: dots
Organization: University of Notre Dame, Notre Dame
Distribution: usa
Date: Mon, 7 Sep 1992 04:16:31 GMT

I saw this puzzle about five years ago in a book called Omni Games Discussiion
or such.  It also discussed the different assumptions people make and how
sometimes it is helpful when facing real world problems to examine your assumptions.  However, like the fellow who originated this dot problem on the net said
it is silly in these problems to follow such a practice indefinitely as an 
infinite number of solutions can be derived.  Anyhow one of the solutions I remember if you check back to the problem (art 6589 on my reel) it doesn't even state that the lines must be connected in anyway so just draw three lines like |||
through the three columns of dots.  Or for one roll the paper into a cylinder
shape and draw one infinitely long line around the cylinder that touches all thedots.  Anyway, while I think the point that the original four line nine dot makes (to check your assumptions) is a good one, but more problems in the same vein
are pointless and irritating when you try to logically solve them only to the
"solution" be illogical.  
just my two cents.

btw I've been home for the summer, where did Senor Mike Steiner go to?


--
Sean Maurer smaurer@artin.helios.nd.edu

Newsgroups: rec.org.mensa
From: ecsd@tfs.com (Eric C. S. Dynamic)
Subject: Re: Since we are on the topic of puzzles ...
Organization: TRW Financial Systems
Date: Sat, 12 Sep 1992 11:49:35 GMT

>Given a simple balance scale, what is the minimum number of weights needed to
>accurately measure an unknown weight between 1 and 100 pounds to within 1
>pound.  To complete this puzzle, list the poundages of each weight you are
>using.

Intuition say Fibonacci series. Eh?
From: Dave.Aronson@p11.f120.n109.z1.fidonet.org (Dave Aronson)
Sender: Uucp@blkcat.UUCP
Newsgroups: rec.org.mensa
Subject: Math Quiz-tion
Date: Fri, 11 Sep 1992 12:32:10 -0500

cjdcosta@eos.ncsu.edu (CHRISTOPHER J DCOSTA) writes:

 CJD> We all know the relationships 

 CJD>     2       2       2
 CJD>    3   +   4   =   5

 CJD> similarly,

 CJD>     2        2      2
 CJD>    5   +   12  =  13

 CJD> etc.

 CJD> But given any arbitrary integer, is it
 CJD> always possible to find two other integers, 
 CJD> so that the three can be related in the
 CJD> same way that (3,4,5) and (5,12,13) and 
 CJD> several other numbers are related ?

Yes.  For an odd one, use half the numbers on either side of its square.  For an
even one, use double the numbers that you would for half of it.


Newsgroups: rec.org.mensa
From: Erik Naggum <enag@ifi.uio.no>
Organization: Department of Informatics, University of Oslo, Norway
Date: 13 Sep 1992 02:36:56 +0200
Subject: Re: A question of conscience? (Was: Why does a person join mensa?)

Kjeld Hvatum <skh4161@mvs.draper.com> writes:
|
|   In fact, I've seen a table in some kind of personnel manual listing
|   maximum recommended IQ's for a number of job categories.  It would
|   render many Mensa members unemployable.

This is consistent with the disproportionately many Mensa members who
are self-employed and who own their own business.  Another way to put it
is that many Mensa members are employers.  I'm not sure that's so bad.

Best regards,
</Erik>
--
Erik Naggum             |  ISO  8879 SGML     |      +47 295 0313
                        |  ISO 10744 HyTime   |
<erik@naggum.no>        |  ISO 10646 UCS      |      Memento, terrigena.
<enag@ifi.uio.no>       |  ISO  9899 C        |      Memento, vita brevis.
From: Dave.Aronson@p11.f120.n109.z1.fidonet.org (Dave Aronson)
Sender: Uucp@blkcat.UUCP
Newsgroups: rec.org.mensa
Subject: Math Quiz-tion
Date: Fri, 11 Sep 1992 13:06:48 -0500

cjdcosta@eos.ncsu.edu (CHRISTOPHER J DCOSTA) wrote:

 CJD> given any arbitrary integer, is it
 CJD> always possible to find two other integers, 
 CJD> so that the three can be related in [a Pythagorean triplet]?

I replied:

 DA> Yes.  For an odd one, use half the numbers on either 
 DA> side of its square.  For an even one, use double the 
 DA> numbers that you would for half of it.

Whoops!  I didn't notice the "other" in the original statement.  If this means
that in a^2 + b^2 = c^2, a <> b, b <> c, and a <> c, this presents opportunity
for a couple of exceptions, which are 0 (unless it's okay for the two "others"
to be the same as each other), 1, and 2.
From: clong@remus.rutgers.edu (Chris Long)
Newsgroups: rec.org.mensa
Subject: Re: A Short Puzzle
Date: 4 Sep 92 22:40:34 GMT
Distribution: na
Organization: Rutgers Univ., New Brunswick, N.J.

In article <1992Sep4.055131.26719@gn.ecn.purdue.edu>, John Mechalas writes:

> You are on the right thread, though not quite right.  This puzzle was created
> by someone (whose name I can't remember offhand) to show how people commonly
> assume information about a problem that is not actually given.

The puzzle was created by a moron who, if brains were dynamite, couldn't
blow their nose.  People will assume anything *reasonable* about a
problem, but nothing more.  That's obvious, but I suppose still an
intellectual challenge to your average psychologist.

> In this case, it is assumed that the frog is starting in square
> three.  But, the problem never states whether or not the frog is
> *starting* to move, or if it is in the *middle* of a move.

The problem also doesn't state that you can't pick up the damn frog
and place him on a square from where it could reach the food, either.
But this isn't a reasonable assumption to make, is it?
-- 
Chris Long, 265 Old York Rd., Bridgewater, NJ  08807-2618

"In a study of schoolboys, an educator discovered a correlation between size
 of feet and quality of handwriting.  The boys with the larger feet were,
 on the average, older."        Wallis & Roberts, _The Nature of Statistics_
Newsgroups: rec.org.mensa
From: radams@BNR.CA (Rodney Adams)
Subject: WARNING! (Re: Since we are on the topic of puzzles ...)
Reply-To: "Rodney Adams" <RADAMS@BNR.CA>
Organization: Bell-Northern Research, Ltd.
Date: Thu, 10 Sep 1992 16:51:35 GMT

In article <1992Sep10.132344.5693@infonode.ingr.com>, crossgl@infonode.ingr.com (Gordon Cross) writes:
|> 
|> Given a simple balance scale, what is the minimum number of weights needed to
|> accurately measure an unknown weight between 1 and 100 pounds to within 1
|> pound.  To complete this puzzle, list the poundages of each weight you are
|> using.
|> -- 
|> 
|> Gordon Cross          UUCP:     uunet!ingr!infonode!crossgl   "all opinions are
|> 111 Westminister Way  INTERNET: crossgl@infonode.ingr.com    mine and not those
|> Madison, AL 35758     MA BELL:  (205) 730-7842               of my employer."

DO NOT POST THE ANSWER TO THIS PROBLEM!!!!!  This problem is found on 
the self-administered Mega Test, for which one can use references BUT
NOT CONSULT OTHER PEOPLE.

If Gordon can prove that he has taken the Mega Test (perhaps by sending
a copy of the score report via snail mail) then perhaps someone could e-mail
the answer, since the test can only be taken once.  However, please do 
not sacrifice the legitimacy of the Mega Test (or others like it) by 
making public any of the answers.  
 
----------------------------------------------------------------------

Rodney G. Adams
The opinions expressed above are not necessarily those of my employer.
As if you didn't already know that....
"If a person offend you, and you are in doubt as to whether it was 
intentional or not, do not resort to extreme measures; simply watch 
your chance and hit him with a brick."                    - Mark Twain
Newsgroups: rec.photo
From: zrepachol@cc.curtin.edu.au (Paul Repacholi)
Subject: Re: Rechargeable batteries
Organization: Curtin University of Technology
Date: Tue, 8 Sep 1992 19:54:30 GMT

In article <1992Sep8.001411.18690@informix.com>, neilw@informix.com (Neil Williams) writes:
> 
> I'm looking for high-capacity AA batteries for my 430EZ flash.  I haven't
> been able to find the Excel brand that pop photo recommended, and none
> of the other brands seem to list the milliamp hour rating.

I wouldn't give too much creadence to PF's recomendation.

> 
> Does anyone know which of the following brands have the highest capacity:
> Millenium, GE, Panasonic, and that price-club brand I can't recall...???
> 
> Any suggestions or advice is appreciated.  
> 
> I've also been assuming the 1.25v rechargeables will work fine in the
> 430EZ; is this a reasonable assumption?
> 

I use Saft KRH 15/51 AAs for my EOS-1 and 430. They are 500mAH. Varta, Sanyo
Eveready (Union Carbide ) are also very good IMHO. Sanyo have up to 800mAHr
in AA now, but pricy, and not the best unless yuo get the high current type.

The trap of NiCds is their habit of self discharge. You always seem to have
one in a set that wants to bite the dust real fast.

You should be able to get copys of the various makers spec sheets with a little
phoneing around. Lots of good info on care and feeding as well.

~Paul
From: dbernard@thewho.Central.Sun.COM (Dave Bernard)
Newsgroups: rec.photo
Subject: Re: High speed useful ? (was Re: Nikon N90 technobabble)
Date: 8 Sep 92 11:49:30 GMT
Reply-To: dbernard@thewho.Central.Sun.COM
Organization: Sun Microsystems

In article 28773@sophia.inria.fr, luong@naxos.inria.fr (Quang-Tuan Luong) writes:
>In article <PHR.92Sep4102515@soda.berkeley.edu>, phr@soda.berkeley.edu (Paul Rubin) writes:
>
>|> They should also add TTL flash metering and a 1/8000 shutter (the more
>|> recent FM2's already use the same shutter as the N8008) and call it
>|> the FM3.
>
>I don't understand the utility of high speed shutters. On my 8008, I think
>I have never shot beyond 1/1000s, and I cannot imagine any real situation 
>where 1/8000s would be useful. Using high speed means that you use also high
>sensibility film, and/or wide aperture, and this is known to reduce 
>significantly image quality.
Supp>Tuan.
Supposedly there's another drawback to shutters featuring very high speeds... there
is much more stuff going on in a much shorter time, making for more vibration... at
least, this is the contention of a recent book I read on low light photography.
Focal plane shutters featuring low flash syncs (1/60 or so) tend to be the best
for low-light, hand-held photography.  FP shutters with high flash sync/high speeds
supposedly rock and roll too much.

	Dave



Xref: sparky rec.photo:15748 rec.backcountry:6903
From: ajayshah@almaak.usc.edu (Ajay Shah)
Newsgroups: rec.photo,rec.backcountry
Subject: What tripod do you use when backpacking?
Date: 8 Sep 1992 12:16:54 -0700
Organization: University of Southern California, Los Angeles, CA
NNTP-Posting-Host: almaak.usc.edu

The title says it all.
What is a good tradeoff between weight and stability?

The worst lens it will be used with is the Sigma 400 APO AF.

        -ans.

-- 
Ajay Shah, (213)749-8133, ajayshah@usc.edu
Newsgroups: rec.photo
From: boh@fraser.sfu.ca (Changhao Boh)
Subject: Shuttlebug subscribstion... Mailing address needed
Organization: Simon Fraser University, Burnaby, B.C., Canada
Date: Sun, 13 Sep 1992 08:15:45 GMT

Hi.  I am wondering if anyone here knows the mailing or FAX (Best !) address
of Shutterbug magazine.

I live in Vancouver, British Columbia, Canana.  A local fax number would be
appreciated.

Thanks in advance, and good health to all.

Changhao.
From: trevor@bcserv.wustl.edu (Creamer (Trevor))
Newsgroups: rec.photo
Subject: Re: 430 EZ flash for Canon
Date: 9 Sep 92 19:06:37 GMT
Organization: Washington University in Saint Louis, MO USA
NNTP-Posting-Host: bcserv.wustl.edu

jchen@smdsctt.bellcore.com (C. Jason Chen) writes:

>In article <1992Sep9.174736.3895@clark.edu>, gsnow@clark.edu (Gary Snow) writes:
>|> In article <1992Sep9.145118.22378@nmr-z.mgh.harvard.edu> alexm@nmr-z.mgh.harvard.edu (Alex Milshteyn) writes:
>|> >Adorama's prise on 430EZ is $220.00 - $100.00 less than Lechmere's,
>|> >and  $80.00 - than Ritz's.
>|> >But they list two different models, which they list as follows:
>|> >430 ez w/Case (Meter) - $204.95
>|> >430 ez w/Case (feet) - $224.95
>|> >What the heck is the difference for AF flash and camera?
>|> 
>|> The diference is that one gives flash ranges in meters, and the other in
>|> feet on the flashes built in LCD display.
>|> 
>|> Gary
>|> 
>In addition, the "meter" version must be grey market. 

When I bought my 430EZ from B+H the guy on the other end of the line
told me up front that the metre-scale model was grey-market. Splurge
and pay the extra $20.
Trevor
-- 
Trevor P. Creamer                  ,-_|\   Dept. of Biochemistry
Email  - trevor@grserv.wustl.edu  /     \  & Molecular Biophysics
Phone  - (314) 362 4105           *_,-._/  Washington University
Fax    - (314) 362 4115                v   St. Louis, Missouri 63110
Newsgroups: rec.photo
From: bbarton@Ingres.COM (Brian Barton)
Subject: On-Camera Flash Diffusers
News-Software: VAX/VMS VNEWS 1.4-b1  
Keywords: diffusers
Organization: ASK Computer Systems, Ingres Product Division
Date: 10 Sep 92 23:55:47 GMT


Could someone please provide some input on the various types of on-camera
flash diffusers that are available?

I've seen all of the info. in the photo mags, so I really do know what's
available.

I guess I'd like to know what people think works best for their applications,
but only for on-camera flash.  I've got umbrellas for my studio work.  

I currently have several "bounce cards" and a Micro Apollo, but I'm seriously
considering getting one of those Sto-Fen "Omni Bounce" diffuser domes for my 
on-camera flash shooting.

Can anyone that owns one comment on how effective they are and if they like
the results they get.

I almost always shoot slide film and I'd be using the Omni-Bounce mostly
outside and at night to cover news events. 

I know it eats more light (2 stops I think) than a bounce card, but my
bounce card technique ruined a bunch of film I shot 'cause the wind was blowing
when I was shooting and I didn't realize that my flash was shooting almost 
straight up into the air with no reflective surface to send it to my subject!

Comments appreciated.

Thanks.

Brian
bbarton@ingres.com 

Newsgroups: rec.photo
From: rhanlon@beta.tricity.wsu.edu (Richard Hanlon)
Subject: Nikon 6006 advanced instead of rewinding
Keywords: Nikon 6006
Organization: Washington State University Tri-Cities, Richland
Date: Sat, 5 Sep 92 04:48:12 GMT

I've only had my Nikon 6006 for about 3 months.  I finished a roll of film and
when I got the new roll of film in, the LCD panel displayed the F-EE.  I
found out later that this meant that the F stop ring was in the wrong
place, but with out thinking at the time, I thought the F was for film, and
that there was an error with the film I had just loaded.  I opened the back
of the camera, and saw that the film was OK.  But just to be certain I
thought I would unload the roll and start over.  I pushed the slide lever
over and pushed the plunger to start the camera rewinding.  But to my
surprise, the camera was advancing the film, not rewinding it.  I managed
to get it to stop (I think) by moving the slider and by pressing the plunger,
but not until it had pulled about 5-7 frames of film out of my film
canister.  

Has anyone else had this problem??  Or is this just a defect in my camera.
Any comments would be appreciated.

Richard Hanlon           Richland WA, USA
rhanlon@beta.tricity.wsu.edu
From: moreaux@litsun22.epfl.ch (Michel Moreaux)
Newsgroups: rec.photo
Subject: Re: Nikkor AIS Recommendation (Was: NIKON AF Wide Angle Recommendation)
Date: 7 Sep 92 09:00:32 GMT
Reply-To: moreaux@litsun.epfl.ch
Organization: Laboratoire d'informatique technique
In-reply-to: jay@metran.UUCP's message of 3 Sep 92 10:56:50 GMT


|hlam@umiami.ir.miami.edu writes:
|: Can any one give me advise and/or recommendation on any of the following
|: Nikon AF wide angle lenses:
|: 
|:       16 mm, 20 mm, 24 mm
|: 
|: I currently own a 28 mm and would like to purchase one of the above.  The 28 mm
|: has been satisfactory but I would like to cover a wider range without having a
|: fish eye effect.
|
|At the moment, the purchase decision for this looks like a long way off for
|me (these lenses are expensive, and based on my experience with my 28mm
|Tamron, I will not settle for anything less than a Nikkor).  I would not
|even bother to ask about it, except that I seem to be in almost, but not
|quite, the same situation.
|
|As I stated, I also own a 28mm (Tamron).  This focal length is just right
|for me; I'm happy to not have a 35 or a 24.  However, I feel a definite need
|for something much wider, in fact, as wide as possible.  But, it is very
|important that the lens be rectilinear and generally free of distortion.
|Do the shorter f.l. "ultra-wide angle" Nikkors, especially 16mm, suffer
|significantly from distortion?  That is my main concern.

Most of the time, manufacturer try to avoid distortion on super-wide-angles,
unlike fish-eyes. Secondly, the Nikon 28 mm AF is not a really good
lens compared to the 28 mm f2.8 AIS lens. That is the main reason why
the AF 28mm is cheaper. Thirdly, it is ridiculous to compare non-Nikon
lenses with Nikon lens since in all the tests I have read and made the
non-Nikon lenses were always worse than the Nikon premiums. You said
that 24mm AF is an expensive lens. I do not really think so because
this lens is a damn good lens. The AF 20 mm is also a good lens
(slightly worse than the Canon 18mm super-wide-angle that costs 4
times more).

I have never heard about a 16mm AF Nikon lens. If I had to buy a Nikon
super-wide-angle lens I would buy the 18 mm AIS lens.

-Michel.
--
------------------------------------------------------------------------------
Michel Moreaux,                           | "Ceux qui ne savent rien en savent
Ecole Polytechnique Federale de Lausanne  |  toujours tout autant que ceux qui
Departement d'Informatique                |  n'en savent pas plus qu'eux"
Laboratoire d'Informatique Technique      |                  P. Dac.
EL-Ecublens                               |___________________________________
CH-1015 Lausanne                           
Phone # : (21) 693-46-72,   e-mail : moreaux@litsun.epfl.ch
------------------------------------------------------------------------------
Newsgroups: rec.photo
From: zrepachol@cc.curtin.edu.au (Paul Repacholi)
Subject: Photo-CD and HDTV 'standards'
Organization: Curtin University of Technology
Date: Sat, 12 Sep 1992 08:53:25 GMT

In article <1992Sep11.125437.4167@kodak.kodak.com>, axman@acadia.Kodak.COM (Mike Axman) writes:
...
> Although the current player is engineered for current television standards,
> the data recorded on the Photo CD is "HDTV ready" when those devices 
                                        ^^^^^^^^^^
> become generally available.  Additionally, you can read the data into 
> a computer using a CD-ROMxa drive, and/or get digital prints of 
> manipulated images.
> 

could you explain this a bit more Mike? Given the state of HDTV 'standards'
and NTSC vs PAL ect...

~Paul