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  2. Staying dry in the rain

    You're right. And it's not much of a puzzle after all. You have to allow Albert to lean forward as he runs to make this puzzle at all interesting. But even then, the obvious solution is to have Albert lie horizontally and crawl at infinite speed. Only the top of his head gets wet then. I ran into this puzzle a few years back and "solved" it, more interestingly but also more incorrectly, by multiplying his front and top areas respectively by sin theta and cos theta where theta was determined by his speed compared to the speed of the rain, and some other stuff. It was nonsense.
  3. Today
  4. Dividend please (on steroids)

    More clues.
  5. New math

  6. The word that won't quit being a word

    Two of the many other possible solutions -- the second of which begins with a 12-letter word, and the first having only the beginning or ending letters being erased, thus not forming words with additional white space within the word.
  7. Code to the safe

    Is it allowable to design a key that can open multiple different locks? If each lock has multiple positions where a subset of the pins at each position (potentially at different positions for each lock) need to be raised to the correct height in order to be opened, then it would be fairly straightforward to design one key for each general while still using the total number of locks in the answers above. If you're limited in how many positions the pins of a lock can be in, then things might get complicated.
  8. Yesterday
  9. The word that won't quit being a word

    There are many possible solutions.
  10. 3 Quickies

    It's just a letter substitution. 1 = A, 2 = B, 3 = C, etc.
  11. 3 Quickies

    I hate to bring this one back up again, but what's the rationale behind #3?
  12. Last week
  13. Take a guess

  14. Take a guess

    Then again...
  15. Take a guess

    This is a fun one...
  16. Same numbers of heads

    @Thalia You are so right. Thanks. Locking this thread.
  17. Take a guess

    Haha, that's kind of fun to wrap your head around...
  18. New math

    flamebirde - last 2 digits
  19. Same numbers of heads

    Think this one has been posted before. EDIT:
  20. Dividend please (on steroids)

    ??? there are 3 digits before green digits , but there are 4 subtraction different from all after
  21. Grabbing marbles

    You are wearing gloves while trying to retrieve the marbles contained in a bag. Because of the gloves, you're doing a pretty poor job of it. With each grab, you are only able to retrieve a random number of marbles, evenly distributed between 1 and n, the number of marbles currently in the bag. With 30 marbles initially in the bag, how many grabs do you expect it will take to retrieve them all?
  22. Same numbers of heads

    Twenty coins lie on a table, with ten coins showing heads and the other ten showing tails. You are seated at the table, blindfolded and wearing gloves. You are tasked with creating two groups of coins, with each group showing the same numbers of heads (and tails) as the other group. You are only permitted to move or flip coins, and you are unable to determine their initial state. What's your plan?
  23. Staying dry in the rain

    For the purposes of this puzzle, consider our old friend Albert to have the shape of a rectangular paralellepiped (when he was born the doctor remarked to his mother, I don't explain them, ma'am I just deliver them) just meaning a solid having (six) rectangular sides. At a recent physical exam, Albert was found to be 2 meters tall, 1 meter wide and .20 meters thick (front to back.) He maintains his geometric rectitude by never leaning forward when he walks or runs. So anyway, Albert, alas, has found himself caught in a rainstorm that has 1000 raindrops / cubic meter that are falling at a constant speed of 10 meters / second, and he is 100 meters from his house. Just how fast should Albert run to his house so as to encounter as few raindrops as possible?
  24. New math

    I think.
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