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Everything posted by superprismatic

  1. superprismatic

    reversed coefficients

    One possibility you hadn't addressed: What about roots which are 0, and possibly with multiplicity?
  2. superprismatic

    Dueling cards

  3. superprismatic

    How big was the dinner table?

    I have one question which could make a big difference. It's a bit indelicate, so I'll put it in a spoiler.
  4. superprismatic

    Dueling cards

  5. superprismatic

    reversed coefficients

  6. superprismatic

    The kindest (shortest) cut of all

    @Bonanova or anyone else who may have an interest in this: Do you have a proof that that circular arc is the shortest? Conceivably, a piece of a trigonometric curve, or exponential curve, or another conic section may be shorter. The possibilities are endless.
  7. superprismatic

    Making 271

    I'll bet that the answer is divisible by 7.
  8. superprismatic

    Birthday Probability

    Nice analysis! I wish I had thought of that.
  9. superprismatic

    Factor this

  10. superprismatic

    Magic octagon

  11. superprismatic

    Magic octagon

  12. superprismatic

    Unlocking doors

  13. superprismatic

    Unlocking doors

    I have 2 questions: 1. Are we to find keys to open all 61 doors? A door need not be locked for us to test a key to it. Or are we to find keys for only the 60 locked doors? 2. If the basement is technically the eleventh floor, then there must be 10 floors above it with 10 rooms per floor. That's a total of 100 rooms plus the office in the basement. Is this correct? If so, shouldn't each above-ground floor have 6 rooms? Otherwise, there would have to be 40 rooms without doors.
  14. superprismatic

    Factor completely over integer coefficients

  15. superprismatic

    Greeting Time

    no, that is 00:00:34 the minute zeros lit as LL Do they always do that? Do the hours also do that sometimes? I think the mechanics of it all should be explained.
  16. superprismatic

    Stick a round

  17. superprismatic

    Numerus Primus Dividus

  18. superprismatic

    Unfaithful wives

  19. superprismatic

    Unfaithful wives

  20. superprismatic

    A tossing game you sure win

    This type of game is widely known as "Penney's Game". The Penney is Walter Penny who made quite a few puzzles in the 60's and 70's. I posted nearly 50 of his puzzles (from unpublished papers of his) a few years ago on this forum. You can look at some of them if you search for Penney on this site. They are quite clever puzzles!
  21. superprismatic

    Priceless pearls