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  2. Whodunit?

    Correct. Dick is asserting that he was out running, and that one of his three brothers has just lied.
  3. Jelly beans join the clean plate club

    Sorry guys, "fuller" should have read "at least as full." Examples always help, so here is an example. a b c 7 9 12 <- 14 2 12 -----> 2 2 24 -> 0 4 24 So { 7 9 12 } is a starting point where a plate can be emptied. Can any { a < b < c } lead to an empty plate? A Yes answer needs proof; a No answer just needs a counter example.
  4. Today
  5. Cubicle Stack #2

  6. Jelly beans join the clean plate club

    I have a doubt to confirm.
  7. Largest unit sphere

  8. Cubicle Stack #2

    Think I found one of the 2 I changed from correct to incorrect. But I think that would leave one of these as still wrong though I can't figure out which. . .
  9. Whodunit?

    Oops, you're right! Sorry!
  10. Whodunit?

  11. Whodunit?

    I think if we're getting into the analysis of the logical AND, we could say that any of them are telling falsehoods. The trees, for example, could have been pear trees instead, so the entire statement would evaluate false. I doubt that's the intention of the puzzle.
  12. Largest unit sphere

    Question: the process shown demonstrates a local maximum for the function, but is there a way to prove that (for instance) at n=1000 it doesn't suddenly reach a new maximum? (I guess what I'm trying to say is, is there a proof, or is the solution presented here just process of elimination?)
  13. Whodunit?

  14. Yesterday
  15. I'm Back

    I never participated in the Brian Dennis series, but I do remember them. Welcome back!
  16. Whodunit?

    For some reason, my spoilers are disappearing. Is that normal? Anyway, I don't think this deserves a spoiler. Lying can refer to placing oneself in a horizontal position, but it is also the act of being untruthful. Incidentally, I can find no evidence that "lieing" is an English word. With that in mind, you could say that Dick has a brother who is currently reclining and nobody murdered anybody in this situation.
  17. Whodunit?

  18. Cubicle Stack #2

    Thalia, I'll check your current numbering later, but ...
  19. On a table are three plates, containing a, b and c jelly beans, in some order, where a < b < c. At any time you may double the number of jelly beans on a plate, by transferring beans to it from a fuller plate. After one such move, for example, the plates could have 2a, b-a, and c beans. Using a series of these moves, Is it possible to remove all the jelly beans from one of the plates?
  20. Cubicle Stack #2

    Oh, jeez, you're right. I dunced that pretty good.
  21. Cubicle Stack #2

    Another stab at it.
  22. Last week
  23. Cubicle Stack #2

    Revision to CCC and EEX with numbers.
  24. Soldiers in a field

    Cannot you shorten it? - if no one else watches A nor B, remove A and B and start over (this happens if A and B are very near and all other are far away enough) - if someone else watches A and/or B, at least one is not being watched (evident; if proof needed, start with 3 and continue with recursion)
  25. Who can go the lowest?

    Not fully calculated because the math gets extremely messy and complicated pretty fast, but a description of how to go about it Although a better answer might be that if there are 10 people playing a game with at least $10 entry fee and $100 payout with a non-zero chance that no one will win and the house will keep everything if everyone ends up picking a number in common with at least one other player, then your best move is to not play.
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