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dgreening last won the day on August 1 2017

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About dgreening

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    Maryland [DC area]

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  1. dgreening

    Simple classic puzzle on profit

    Pickett makes a good point about not knowing the original price that Bill paid, but based on the data as presented
  2. dgreening

    A bug problem

    Sorry, something got lost in copying and pasting. The site does not like the formatting used in word, so I am attaching a picture of the solution ... apologies in advance.
  3. dgreening

    A bug problem

    A friend and I were working on this. Mark came up with an elegant solution. Close-form (explicit function) solution: .
  4. dgreening

    A perfect lamp

    This is very interesting, but I think there is a more concrete answer.
  5. dgreening

    Spin the bottle (no kissing involved)

    My first thought was like Capt Ed. BUT thinking about it some more.
  6. dgreening

    gambling strategy

    No dispute here.
  7. dgreening

    Precision Dornicks

    Aha! I just didn't follow the same process through to get the supper precision devices! Thanks
  8. dgreening

    gambling strategy

    Curious about your result. If you average over many trials are your expected winnings positive? As I mentioned, I only did a small number of runs [about 100]. BTW - I like your title "Retired Expert"! I think that if you do a large number of runs, you eventually get to about 50%. I was quoting bonanova solution/answer, not my proposed strategy. Your strategy is not applicable, you can't bet more money than you have, if your current money is 50$, your original money is 100$, so 2*100-50 = 150$, which you don't have. Now I explain, my proposed strategy. Hidden Content yes, if you [and the house] are willing to bet micro, nano or pico dollars, then the game can go on forever. But your money is gone, so it is theoretically correct, but not very practical.
  9. dgreening

    Precision Dornicks

    An answer for part 1
  10. dgreening

    Code needs testing.

    Perhaps some more description of the task would help. What is the context for this question??
  11. dgreening

    gambling strategy

    Now I am confused. I think I followed the strategy you described yesterday, when you postulated that it would deliver 100% chance of winning. But, now your simulation it gives you a 50% chance of winning. Did I miss something??
  12. dgreening

    gambling strategy

    I was working on the strategy that you describe: Bet half my money [rounded to an integer]; orbet the "ceiling" [twice my original money - Current money].Testing this in a spread sheet [with only about 100 trials] I am winning about 62% of the time.
  13. dgreening

    Serial numbers...but!

    The hint about primary numbers did not help, but I noticed a pattern
  14. dgreening

    How big is the ladder

    I would be interested in how you calculated your answer. I came up with something slightly different