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Next door neighbours

  1. Jul 1, 2004 #1
    i have another one for all of you.
    the question itself is not that difficult (at least i think so) but the challenge here is to complete it as fast as possible.

    it took me about 20 minutes, let's see how long does it take you to solve it. i believe you can do much better.

    here it goes-

    Sarah, Hope, Ellen, Rosanna, and Lucy are five neighbors on Kaser Street. Each one lives in a differently colored house: red, blue, yellow, green, or white. Each also has a different number of children (1 through 5), is of a different nationality (United States of America, United Kingdom, Australia, France, Canada), and has a different road sign in front of her house (Stop, Hospital, Speed Limit, One Way, Railroad Crossing). By using the clues below, you will be able to figure out where everyone lives, and their house color, number of children, nationality, and road sign.

    1. The Canadian's two next door neighbors are the woman with the Hospital sign and the inhabitant of the White house.
    2. The women who have 2 and 3 children are NOT next-door neighbors.
    3. Rosanna's two neighbors are the woman from France and the woman who raises 2 children.
    4. The household with 5 children is west (left) of the One Way sign.
    5. The house with the Stop sign in front of it is NOT next to a house colored yellow.
    6. The French woman and the woman from the United States are next-door to each other.
    7. Ellen is an Australian who likes to post on the message board at www.physicsforums.com.
    8. The woman in the red house, who is from the United Kingdom, sure is glad she gets BBC America on cable, as she and her 5 children like watching Changing Rooms on it.
    9. Lucy absolutely hates her yellow house, but can't afford to paint it.
    10. The American lives west (left) of the woman from the United Kingdom.
    11. Sarah's two next door neighbors are the woman with 5 children and the woman with a Speed Limit sign in front of her house.
    12. Hope is NOT the woman whose two next-door neighbors are the woman with 4 children and the woman whose house is blue.
    13. The One Way sign is in front of Hope's house.
  2. jcsd
  3. Jul 1, 2004 #2
    Did it take you 20 minutes to realise it is not possible? It took my 42 minutes to get to an answer to find it was wrong. I have tried a number of combinations and none work. Is it possible because I say it is not.

    The Bob (2004 ©)

    P.S. Knowing my luck I am wrong and I have made a fool of myself. :tongue2:
  4. Jul 2, 2004 #3
    believe me, it is possible.
    i have succesfully solved it, though at one point of time i also thought that it cannot be solved but then i realised my mistake and after that it was a lot easier.

    i guess that you are making the same mistake, give it another try, and this time be a bit more careful.

    carefully check if you are reading the clues correctly, because i think you are making a mistake in interpreting what a particular clue is telling you.

    P.S. trust me, it can be solved.
  5. Jul 2, 2004 #4
    Oh ok. I will try again.


    The Bob (2004 ©)

    P.S. The last 42 minutes don't count :tongue2:
  6. Jul 3, 2004 #5
    ideally they should, but as i don't find many people trying this puzzle, i will make an expection. :biggrin:
  7. Jul 3, 2004 #6
    Cheers :biggrin:

    The Bob (2004 ©)
  8. Jul 3, 2004 #7
    Hmmm... maybe it's my turn now to make fool of myself, but anyway, i'll try to find the truth :)))
    so it took me 10 minutes (during the first 7 minutes i was trying to remember the names ;) ) to realize that there is really no answer. The other 12 minutes i spent on re-checking it...
    could you please check if all of the conditions are stated correctly?
    if needed, i can post what i got, but i hope it won't be neccesary...
    + one question: i assumed that "left of" doesn't imply "near neighbour" (however they still may be near-neighbours)
    but that actually changes nothing - the answer is still "impossible"...
  9. Jul 3, 2004 #8
    Yer I agree. I get it right in my eyes then changed it and then applied the results and the original correct statments were in correct. We are simply asking you check the statements. We are not saying you are wrong.

    The Bob (2004 ©)
  10. Jul 3, 2004 #9
    that is right, "left of" does not neccessarily mean the next door neighbour, and to tell you honestly, this was where i was making a mistake while tryng to solve it myself, but once i realised this i was able to solve this.

    and YES i have checked all the conditions, they are correct and just for you, i have rechecked my answer and it is coming out to be correct.

    i did believe that you were making the same mistake as i was, but i guess every person can come up with their own different mistakes in the same question.

    P.S: i now hope that someone else will surely be able to solve it. :wink:
  11. Jul 3, 2004 #10
    Thanks a lot! :approve:

    may be... :redface:

    well, i'll try once more... :rolleyes:
  12. Jul 3, 2004 #11
    hmm... the following satisfies the clues, but...
    from left to right in that way: a-b-c-d-e

    a = USA, Lucy, yellow, speed limit, 3 children
    b = France, Sarah, blue, rail-road crossing, 4 children
    c = UK, Rosanna, red, hospital, 5 children
    d = Canada, Hope, green, 2, one way
    e = Australia, Ellen, white, 1, stop

    ... but, for example if we exchange children von Lucy and Sarah - nothing will happen! the clues will be satisfied :)
    is it?
  13. Jul 4, 2004 #12
    so hemmul has finally come up with an answer which seems to satisfy all the cnditions.

    yes you are right here also, infact even if you interchange the colours "blue" and "green", still it would make no difference.

    But i would like to know what mistake you were making, coz i can't think of any other than mine.

    P.S: you forgot to mention how much time it took you to solve it, be honest, and add up all the time you had spent on this puzzle. i'm sure you can't beat my time. :biggrin:
  14. Jul 4, 2004 #13
    and what about you Bob, do you still think that it is not posible.
    Time for self analysis my friend.
  15. Jul 4, 2004 #14
    Yer ok. I knew it was possible because you set it up mate. :wink: But I made that mistake above (to the left as i next door neighbour when it isn't necessarily). So I will do it again (as I have not really read the answers that hummel gave). I will see what I can do now but I am sorry. I knew I was wrong. :cry: ( :rofl: )

    The Bob (2004 ©)
  16. Jul 4, 2004 #15
    My "mistake" was an assumption that there is single answer to the problem - i was trying to solve it step by step, scrolling all the clues (at each iteration) to find the next most useful one... that took a lot of time... but, as it turned out to be more than one correct answer to the problem, i now understand that that way wasn't the best strategy... in fact 3 min before i posted the last answer i decided to make some random assumptions, that were actually correct (e.i. i found one of the answers)...

    be quite, man, i didn't beat you time ;)
    look my first post was at: 07:46, and the last one at: 01:47... :rofl:

    so, i have one question...
    it was the first problem of this kind i decided to spend time on... and i have always thought that these problems have single answer that is to be derived via a strong chain of logical assumptions... but now i see that at a certain point you have to make a random "move"... isn't that brutal? :biggrin:

    edit: corrected some grammar mistakes, and added more ones ;)
    Last edited by a moderator: Jul 4, 2004
  17. Jul 4, 2004 #16


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    Hemmul, you made an error. I think the mistake you made is:

    12. Hope is NOT the woman whose two next-door neighbors are the woman with 4 children and the woman whose house is blue.

    The wording means that a woman with neighbours 4 children and blue does exist, but Hope is not she. So your solution does not fit.

    Correct solution, as far as I can see, is:

    House 1: US, Yellow, 3, Lucy, Speed limit
    House 2: France, Green, 4, Sarah, Railroad
    House 3: UK, Red, 5, Rosanna, Hospital
    House 4: Canada, Blue, 2, Hope, One Way
    House 5: Australia, White, 1, Stop

    (Copy and paste into notepad to read)
    I spent about 15 mins on it, and I promise I didn't read anyone else's post first.
    Last edited: Jul 4, 2004
  18. Jul 4, 2004 #17
    It's definitely a wise idea to interpret the 12th clue like that - e.i. the woman with such neighbours does exist. But such a "plugin" just filters out the set of all possible answers. And my answer turned out to be one of the filtered ;) Reason? As i mentioned at some point i just started making "random moves", and it came out that one of my moves is "against" the alternative interpretation of 12th clue...
    I didn't check Your answer, as i trust that it is correct, but note, that neither Your solution is single! Swapping 3 and 4 children infirst two houses gives another solution ;)l

    edit: just some spelling... ugh... something happened to my english today ;)
    Last edited by a moderator: Jul 4, 2004
  19. Jul 4, 2004 #18


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    No, because then Rosanna would not have a neighbour with 4 children, and a neighbour with blue houses. As far as I can see, my solution fulfills all rules, and is unique in doing so.
  20. Jul 5, 2004 #19
    Ok vikasj007. The Bob has done it. My mistake was taking that to the left meant next door neighbours. Here is what I got. Doing the same as FZ+ so no one can cheat if they don't want to.

    House 1: Lucy, Speed Limit Sign, Yellow House, 4 Children and American
    House 2: Sarah, Railway Crossing Sign, Blue House, 3 Children and French
    House 3: Rosanna, Hospital Sign, Red House, 5 Children and U.K.
    House 4: Hope, One Way Sign, Green House, 2 Children and Canadian
    House 5: Ellen, Stop Sign, White House, 1 Child and Australian

    I believe there is another combination which involves swapping some children around but I cannot be bothered to post it.

    This took me 22 minutes to do (while watching TV) and 3 minutes to check (although I was sure in the first place because that is how I work). So I did it in 25 minutes. Not bad for me. :rofl:

    The Bob (2004 ©)
  21. Jul 6, 2004 #20
    yeah, that makes sense ;)
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