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#1 2013-04-03 14:41:10

Agnishom
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From: The Complex Plane
Registered: 2011-01-29
Posts: 14,191
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Einstein Puzzles

They give me a headache.

How do you solve them?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Humanity is still kept intact. It remains within.' -Alokananda

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#2 2013-04-03 19:02:50

bob bundy
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Registered: 2010-06-20
Posts: 6,092

Re: Einstein Puzzles

hi Agnishom,

See http://www.mathisfunforum.com/viewtopic … 83#p242683

bluemist never responded to my offer.  So the offer is now transferred to you.  smile

Phro has a similar method.  Trying to find another way now.......

Got it.  Post 11 in http://www.mathisfunforum.com/viewtopic … 19#p220719

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#3 2013-04-03 20:13:09

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,809

Re: Einstein Puzzles

I think I better subscribe.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#4 2013-04-03 22:55:45

bob bundy
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Registered: 2010-06-20
Posts: 6,092

Re: Einstein Puzzles

hi Stefy,

OK.  Choose a puzzle.  (note: I have a solution to the one I've linked.  Have that one if you want to be sure I can do it.  Choose another if you want to set me a challenge.  dunno )

(medical note:  I'm offering help with solving; not help to avoid headaches!  You may still get one. dizzy )

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#5 2013-04-04 00:20:37

Agnishom
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From: The Complex Plane
Registered: 2011-01-29
Posts: 14,191
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Re: Einstein Puzzles

What software is that? Which phro is using?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Humanity is still kept intact. It remains within.' -Alokananda

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#6 2013-04-04 00:23:26

ShivamS
Member
Registered: 2011-02-07
Posts: 3,370

Re: Einstein Puzzles

Excel.

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#7 2013-04-04 00:30:49

Agnishom
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From: The Complex Plane
Registered: 2011-01-29
Posts: 14,191
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Re: Einstein Puzzles

bob bundy wrote:

I am asking about this one


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Humanity is still kept intact. It remains within.' -Alokananda

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#8 2013-04-04 00:57:37

bob bundy
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Registered: 2010-06-20
Posts: 6,092

Re: Einstein Puzzles

Ah!  That one has been much discussed.

This puzzle was first thought up by Zoe Reader in 2006.

Unfortunately, there was more than one solution (3, I think), so Phro and I worked on a revision which is the one posted at

http://www.mathsisfun.com/puzzles/who-l … city-.html

But then puzzlers discovered a second solution to that, so it was back to the drawing board.  The version worked out by Phro seems to have a unique solution (three of us have independently tried it) but it has not yet been posted by MIF.  I think, if I use it now, and you and Stefy are also satisifed that the solution is the only one possible, we can then ask MIF to make it 'official'.

Here are the clues:

1. The person in the middle watches Desperate Housewives
2. Bob is 46
3. The person who watches the Simpsons is next to the person who lives in a youth hostel
4. The person going to Africa is behind Rachael
5. The person who lives in a village is 52
6. The person who is going to Australia has straight hair
7. The person travelling to Africa watches Desperate Housewives
8. The 14-year-old is at the end of the queue
9. Amy watches Eastenders
10. Eilish doesn't live on a farm
11. The person heading to Italy has long hair
12. Keeley lives in a village
13. The 46-year-old is bald
14. The fourth in the queue is going to England
15. The people who watch Desperate Housewives & Neighbours are standing next to each other
16. The person who watches Coronation Street stands next to the person with an afro
17. The 21-year-old lives in a youth hostel
18. The person who watches Corrie has curly hair
19. The 81-year-old isn't going to England
20. The person who is travelling to France lives in a town
21. A person next to Rachael has an afro
22. The person who watches Neighbours has long hair

Got to google 'furniture' will be back to finish this later.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#9 2013-04-04 01:06:44

Agnishom
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From: The Complex Plane
Registered: 2011-01-29
Posts: 14,191
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Re: Einstein Puzzles

From 2, you are 46

But anyway, I just wanted to know which software Phro was using?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Humanity is still kept intact. It remains within.' -Alokananda

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#10 2013-04-04 01:25:42

bob bundy
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Registered: 2010-06-20
Posts: 6,092

Re: Einstein Puzzles

I wish!  smile

He uses Excel, same as me.  So do you want a walk through solution ?

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#11 2013-04-04 01:40:23

Agnishom
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From: The Complex Plane
Registered: 2011-01-29
Posts: 14,191
Website

Re: Einstein Puzzles

Yes, but does excel look like that? That worksheet?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Humanity is still kept intact. It remains within.' -Alokananda

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#12 2013-04-04 01:42:59

ShivamS
Member
Registered: 2011-02-07
Posts: 3,370

Re: Einstein Puzzles

Excel, with the great formatting skills of phronister, can become like that.

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#13 2013-04-04 01:45:24

Agnishom
Real Member
From: The Complex Plane
Registered: 2011-01-29
Posts: 14,191
Website

Re: Einstein Puzzles

Okay, looks great but doesn't mean anything if one is nt intelligent enough


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'Humanity is still kept intact. It remains within.' -Alokananda

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#14 2013-04-04 10:57:54

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,811

Re: Einstein Puzzles

Hi all,

And Bob, I know you're aiming at doing the walk-through - with your method, no doubt...which I'd like to see - but I thought I'd post my method as well in case it might help in some way or other.

So......here is an image of the worksheet I used for this puzzle. It includes a section at the bottom for entering the solutions as you find them. It can be printed (in 'landscape' orientation) to work on away from the computer. 

It's a much simpler layout than the one in post #7, and also uses a much simpler solution strategy - ie, 'process of elimination' ("PoE").

With PoE I use a working grid that contains bold identifying letters/numbers (usually the first letter/number of the group's options) - see image.

You eliminate all elements in the working grid that are false, and the last option left standing in a particular group is that group's solution.

If using a spreadsheet, just highlight the cell to be eliminated and press 'Delete' to remove the entry, and if using pen and paper just scribble over the false element. For clarity, solutions should be entered in the empty grid below the working grid.

When you find a solution, delete all false elements (ie, those that have the same starting letter/number as the solution) in that same row.

Sometimes the clue gives a group's solution outright (eg, Clue #1), in which case the job is easy, but mostly you'll need to scan the clues (maybe several times) to find the next element to be eliminated, or sometimes even to find a group's solution following a successful line of reasoning.

I also use visual aids such as:
- Spreadsheet: grey out solved clues; fill the cell of used-but-not-solved clues with a light colour.
- Pen & paper: rule out solved clues; put a dot alongside used-but-not-solved clues.

You might find other helps, or ones that suit you better.

Post #7's layout and strategy - the 'ticks and crosses' ("T&C") method - is the one you usually find in logic puzzle books and magazines and is extremely time consuming. But it gets the job done...eventually.

I no longer use T&C and much prefer PoE, with which I can solve this puzzle in a fraction of the time that it takes with T&C. That being so, PoE has helped me greatly with revising this puzzle to find this version that now has just one solution (we think! - but we're pretty confident about that)...and it has also helped me enormously with revising pRo9aMeR's tough 'Who has the purple door' puzzle to make it even more difficult and interesting than it was, something I couldn't have done inside 10 years with T&C.

View Image: Who lives in the city.png

Last edited by phrontister (2013-04-05 17:59:36)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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