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Sixty men can dig a post-hole in one second

  1. Jan 24, 2015 #1

    Stephen Tashi

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    Whenever, I see those elementary algebra word problems about "rates of work", I think of Ambrose Bierce's definition of Logc:

    (Quoting it from https://www.uta.edu/philosophy/faculty/burgess-jackson/Ambrose Bierce (Logic).pdf )

     
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  3. Jan 24, 2015 #2

    mfb

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    Usually, those problems use numbers that are not so unrealistic. Sure, you cannot scale it arbitrarily, but that should not be surprising.
     
  4. Jan 24, 2015 #3

    Vanadium 50

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    My favorite version of this: "It takes a 40-piece orchestra six minutes to play a particular Strauss waltz. How long will it take a 60-piece orchestra to play the same waltz?"
     
  5. Jan 24, 2015 #4
    Lol at Mr V
     
  6. Jan 24, 2015 #5

    Matterwave

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    40*6/60=4 minutes. I'm so good at these problems, I breeze right through them. :)
     
  7. Jan 24, 2015 #6
    Must have left the waltzers panting...
     
  8. Jan 24, 2015 #7
  9. Jan 24, 2015 #8
    I might be completely wrong here, but aren't larger orchestras usually employed for slower pieces, and thus the 60-piece orchestra might be conducted at a slower tempo? So there may be something to that.
     
  10. Jan 25, 2015 #9

    mfb

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    "Okay, there are 6000 notes left to play. You take the first 100, you take the second 100, ...
    Go!"
     
  11. Jan 25, 2015 #10

    Ryan_m_b

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    I'm fairly certain it was D H I read this from but I tend to use "9 women cannot make a baby in one month"
     
  12. Jan 25, 2015 #11

    Matterwave

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    Interestingly enough, if you have enough people in the band, you can reach a singularity where the whole piece is played before the conductor even finishes conducting the first downbeat.
     
  13. Jan 25, 2015 #12

    PeroK

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    Syllogism arithmetical, in my experience, is applied frequently by IT project managers. This is contrary to Brooks' law (from "The Mythical Man-Month") which states that adding resources to a late IT project will make it later!
     
  14. Jan 25, 2015 #13

    DaveC426913

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    My favorite has always been Hofstadter's Law: It always takes longer than you expect, even when you take into account Hofstadter's Law.

    (Hofstadter is a big fan of Godel and Escher)
     
  15. Jan 25, 2015 #14

    davenn

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    He must have done work with Murphy. As one of his laws states....
    Nothing is as easy as it looks, everything takes longer than expected and if anything can go wrong, it will, at the worse possible moment
     
  16. Feb 2, 2015 #15

    BobG

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    I wonder how many guys were in this guy's kitchen?



     
  17. Feb 2, 2015 #16

    Matterwave

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    It takes one man 20 minutes to make grits, so there must have been 20/5=4 men in Mr. Tipton's kitchen. NEXT!
     
  18. Feb 2, 2015 #17

    Simon Bridge

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    With 9 women, you can get 9x the usual expected baby production rate.
    You can organize them so you get 9months to the first baby, then one a month for the next 8... or just have this huge burst of productivity after 9 months.
    With the possibility for simultaneous delivery, the production rate can get arbitrarily high.

    When the premize is faulty, the logical result is also faulty... though still logical.
    I think we all know this.

    Ive seen smart replies to rates of work problems phrased like: your dad and your uncle build chairs...
    ... the reply goes: takes forever cause dad and uncle never did get along... or something.
     
  19. Feb 3, 2015 #18

    Ibix

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    One of Heinlein's characters deadpanned that more than a few newly-wed women were so eager for their first child that they manage to produce one in only three or four months.

    A short essay on why the model fails might make an interesting follow-up question. Some tasks can be split up and parallelised, some can't, and some can to some extent. Understanding the limits of your model is at least as important as being able to manipulate the model in the first place. Teaching this along with models might even put to rest some of the "...science...gets such wholesale returns of conjecture out of such a trifling investment of fact" (as Twain put it) comments. (There is no "naive" smiley...)
     
  20. Feb 4, 2015 #19

    BobG

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  21. Feb 4, 2015 #20

    mfb

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