Bad Dog brain teaser!

Discussion in 'Bad Dog Cafe' started by Junkyard Dog, Mar 13, 2019.

  1. Junkyard Dog

    Junkyard Dog Tele-Afflicted

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    This one has been around for nearly 100 years, but I just came across it today. Here's how it goes...

    There's a column of soldiers a mile long walking along at a uniform and constant pace. A messenger is sent from the front of the column to deliver a message to the rear of the column and immediately return to the front. The messenger travels at a constant pace, and upon the messenger's return to the front, the column has covered it's own length. How far does the messenger travel?

    I have the answer (along with the way I solved it...probably are multiple ways), and I'll post it a little later on.
     
    Last edited: Mar 13, 2019
  2. Muinarc

    Muinarc TDPRI Member

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    zero, a column is vertical :p
     
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  3. Shuster

    Shuster Tele-Afflicted Silver Supporter

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    I'm not sure, but I still prefer McDonalds fries:)
     
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  4. flathd

    flathd Poster Extraordinaire

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    Just a guess, but all the way ro the front?
     
  5. Junkyard Dog

    Junkyard Dog Tele-Afflicted

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    I just got a PM telling me this is easily solvable, which is correct.
     
    Last edited: Mar 13, 2019
  6. Boubou

    Boubou Doctor of Teleocity Gold Supporter

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    Depends how you measure.
    He travelled 2 columns
     
  7. Jupiter

    Jupiter Telefied Silver Supporter

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  8. Muinarc

    Muinarc TDPRI Member

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    ok, via e = mc², the messenger is younger than the members of the column when he returns to the front.
     
  9. flathd

    flathd Poster Extraordinaire

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    Measure twice, cut to the front.
     
  10. Chunkocaster

    Chunkocaster Friend of Leo's

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    Two miles like Jupiter said. Speed is not a factor.
     
  11. flathd

    flathd Poster Extraordinaire

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    Too salty, IMO.
     
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  12. Junkyard Dog

    Junkyard Dog Tele-Afflicted

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    It is not 2 miles.
     
  13. Chunkocaster

    Chunkocaster Friend of Leo's

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    2.5 to 3 miles. I just got up and now there's smoke coming from my ears.

    2 miles and a bit.
     
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  14. Shuster

    Shuster Tele-Afflicted Silver Supporter

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    Tell them no salt, so they have to fry you fresh ones;)
     
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  15. ClashCityTele

    ClashCityTele Tele-Meister

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    At a constant pace the messenger would walk half a mile to reach the rear of the column as they are approaching him at the same pace. Then at a constant pace he would never return to the front - he would be walking alongside the guys at the back all day. Surely it's impossible to calculate without the speed of the column or the speed of the messenger? PS I play guitar & drink beer - I'm not a mathematician lol.
     
  16. Shuster

    Shuster Tele-Afflicted Silver Supporter

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    A Column can only be a mile tall, and the soldiers wouldn't be moving an inch because their stacked on top of each other, and the front of the column to the back is determined by it's width.
     
    Last edited: Mar 13, 2019
  17. Muinarc

    Muinarc TDPRI Member

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    It's 1.5 miles but I'm not telling tdpri the secret!
     
  18. Junkyard Dog

    Junkyard Dog Tele-Afflicted

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    Not 1.5, 2, or 3 either.
     
  19. Boubou

    Boubou Doctor of Teleocity Gold Supporter

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    Walked one column length going to the back, one going to the front.
    1+1=2 columns
     
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  20. Junkyard Dog

    Junkyard Dog Tele-Afflicted

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    You're on the right track by breaking it down into the two trips! Keep thinking though. It's not 1 + 1. The column is moving, so it's shorter than a column one way and longer the other.
     
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