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Everything posted by bonanova

  1. bonanova

    The triangle puzzle

  2. bonanova

    Strange math problem

    The professor writes a problem on the whiteboard, thus: 25 - 55 + (85 + 65) = ? He then inexplicably states that, even though you might disagree, the correct answer is actually 5! Explanation?
  3. bonanova


  4. bonanova

    The triangle puzzle

    Very nice! There is another solution that ends two moves earlier, leaving pegs only on the edges.
  5. bonanova

    Best words

    Have fun with this one. A bull stands in a pasture, unaware that he has just swallowed a time bomb that is due to explode in five minutes. Which word best describes the situation? Awful Abominable Dreadful Shocking Five minutes have passed, and all that's visible from the above scene is a sizable hole in the ground and scraps of bone and flesh. Which word best describes this situation? Amazing Silly Messy Noble
  6. bonanova

    Poisonous apples

  7. bonanova

    Poisonous apples

    The OP does not say how many apples there are. It says the proportion that are poisonous. Question: was that the intent?
  8. bonanova

    Poisonous apples

  9. bonanova


    Yes. .
  10. bonanova

    Squares on a plywood

    Doctoring the figure a bit (while I think about solving it.) o - o - o - o - o | / o o o o | / o - o - o Question: You mention the number of nails (12) and also the number of nails in the perimeter (here that's 10.) So for this example, would we be given N=12 or N=10? I'm thinking the latter, but would like to confirm.
  11. bonanova

    9-Balls Cue

    Welcome back TSLF. Nice puzzle!
  12. bonanova

    Killer quickie

  13. bonanova

    Walk the pattern

    Looks like
  14. bonanova

    Walk the pattern

    With that interpretation,
  15. bonanova

    Walk the pattern

    Assuming the above, we note that
  16. bonanova

    Walk the pattern

    Just to be clear, n = 3 4 5 7 8 9 11 12 13 ..., and CW and CCW alternate untethered (my new favorite word) to parity?
  17. bonanova

    Twins birthday puzzle

    A few years back while visiting friends, we celebrated the birthdays of their identical twin daughters Joan and Jane, born just 5 minutes apart. Joan had her party on Sunday, and Jane had hers on Wednesday. Explanation?
  18. bonanova

    Twins birthday puzzle

    Nice solve. And the "few years back" is actually two years ago, when Feb 28 was Sunday and March 2 was Wednesday.
  19. bonanova

    Random passengers

    Al and Bert are among 100 passengers assigned to one hundred seats on an airplane. Al was first to board, and Bert was last. Strangely, the first 99 passengers ignored their boarding passes and took random unoccupied seats. Bert liked the seat he was assigned and is not happy with the situation. If he's lucky, his seat is unoccupied and there's no problem. Otherwise, he insists the passenger erroneously occupying it move to his own assigned seat. The displaced passenger must then move, possibly displacing another person. This process continues until all passengers are seated. What is the probability that Al must move?
  20. bonanova

    Random passengers

    This was my take.
  21. bonanova

    Random passengers

    Nice. One thing I liked about this puzzle is that it's open to clear thinking. Even tho at first it seems too complex.
  22. bonanova

    Comparing a rectangle to a circle

    But actually ...
  23. bonanova

    Comparing a rectangle to a circle

    It certainly should. It clearly fails a units check. Good catch.
  24. bonanova

    Poisoned Needles

    Do any of the clues imply that the indicated needles are adjacent? I would take "on the left side of" to imply that "pain" is adjacent to "seek," while "to the left of" simply means "the other pain" is not to the right of "interesting little creation." But I'd like to be certain of that. Also, is "interesting little creation" one of the needles? If so, you have described nine, not eight, needles. Thanks.
  25. You have 10 sets of ten coins. One set of the ten is counterfeit, the others are genuine. The genuine coins weigh exactly 0.10 ounces. The counterfeit coins are exactly a 0.01 ounces off, making the entire set of ten coins 0.10 ounces off. You may use an extremely accurate digital scale only once. How do you determine which set is counterfeit?