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Posers and Puzzles

Posers and Puzzles

  1. 02 May '05 20:33
    Suppose there are three houses (A,B,C) in a row. The owner of house A lives directly across from the gas company; owner B lives directly across from the water company; and owner C lives directly across from the electric company.

    The homeowners all want to receive direct, uninterrupted connections from each utility station, but they do not want any of the utility lines to cross each other. How will this be accomplished?
  2. 02 May '05 20:36
    can the pipes bend?
  3. 02 May '05 20:52
    Originally posted by richy15
    can the pipes bend?
    yes
  4. 02 May '05 20:57
    well dats easy den, they just bend around everything
  5. 02 May '05 21:08
    Originally posted by richy15
    well dats easy den, they just bend around everything
    not sure what you mean...when i say the lines cannot cross i mean that the projections of the utility lines onto the same horizontal plane cannot intersect each other. thus my requirement may be more stringent than what you had in mind.
  6. 02 May '05 21:25
    Originally posted by davegage
    not sure what you mean...when i say the lines cannot cross i mean that the projections of the utility lines onto the same horizontal plane cannot intersect each other. thus my requirement may be more stringent than what you had in mind.
    The only way to do this in the plane is if a line passes through a house.
    Otherwise, it can be done on the surface of a torus.
  7. 03 May '05 16:08
    Originally posted by davegage
    Suppose there are three houses (A,B,C) in a row. The owner of house A lives directly across from the gas company; owner B lives directly across from the water company; and owner C lives directly across from the electric company.

    The homeowners all want to receive direct, uninterrupted connections from each utility station, but they do not want any of the utility lines to cross each other. How will this be accomplished?
    May I go around the world?
  8. 03 May '05 16:18 / 1 edit
    Originally posted by Siebren
    May I go around the world?
    The trick must be that the electricity, water and gascompany don't stand aside. But are for example Gas at east, Water at north and the electricity at south of the houses. However I can't do it without directing a few pipes around the world.

    To make my answer even more stupid. I am a manager of a large energycompany :'( I'm reconsidering my career now....
  9. 03 May '05 17:32
    Originally posted by Siebren
    The trick must be that the electricity, water and gascompany don't stand aside. But are for example Gas at east, Water at north and the electricity at south of the houses. However I can't do it without directing a few pipes around the world.

    To make my answer even more stupid. I am a manager of a large energycompany :'( I'm reconsidering my career now....
    LOL....Didn't mean to erode your faith in your occupation.

    You could try running the lines around the world (I wouldn't recommend this approach at your next board meeting, though); but I think you may still run into some problems because of the way we have defined what it means for two lines to cross, ie., the problem becomes planar again in the end.

    the trick, as THUD alluded to, is that it's important to remember that the houses are not point sources.