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bonanova

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Everything posted by bonanova

  1. Celebrity Interview

    Well the author has now been outed. Suspect others had it as well. But the message still has to be cracked. Think logically. Good job.
  2. Must have been nice to have a unique solution appear like that. I'm working on a truth-teller puzzle based on the recent US election. Going through the same process.
  3. It was surprising to find that there is only one solution. Here's how I found it. It's computationally challenging - brute force is possible, but I took it as a challenge to solve it efficiently. Even so, aside from guessing, there is no way to avoid evaluating the expression ((AoB)@C)%D for all 9x8x7x6=3024 variable permutations and all 6x5x4=120 operator permutations, 362880 computations in all. But I only did each once. Next I noticed that not all the results were valid. It turns out there are only 3928 valid expressions - about 1.1% of the cases. But all 362880 have to be evaluated to determine that fact and find the valid ones. Each valid expression represents a candidate for a side of the triangle. I put the results into a table. No further calculations were necessary. The first 15 rows (candidate sides) look like this: A solution to the triangle is a set of three sides that "Connect" at their end values (and ops) Use all the values Use all the ops Share a common expression value (equal to the product of the three corners) There were 60 valid results for the expressions: And the full table did not have to be searched. Only segments of the full table had to be searched: those records with a common result. For example, the 2 sides that evaluated to 240. Or the 13 sides that evaluate to 252. Or the 79 sides that evaluate to 45. That is the only solution.
  4. Celebrity Interview

    Not surprised. I wondered whether this belonged in the riddles section. It's both that and logic. Happy belated thanksgiving.
  5. Celebrity Interview

    Obscure clue:
  6. The Donny Hall puzzle

    Around World Series time recently, (that's the American baseball championships for our international Denizens) I asked the question, dressed as a probability puzzle, "Given that you could pick one of the best-of-seven games in the series that you could guaranty to win, which game would that be? I even flavored the question with the opinions of experts that the pivotal games are often taken to be game 3 or game 5, as statistically these games correlated well with the eventual winner. And many responded with one of those choices for their answers. But the correct answer of course is game 7. (Or as some said, the Last game.) So I also like the "one with the car" choice.
  7. Another hat problem

    Adam, Bill and Charlie stood in a line with Adam in front and Charlie at the rear. Charlie could thus see both Adam and Bill, Bill could see Adam, but Adam could not see either Bill or Charlie.Their teacher brought out a box containing three red hats and two blue hats. She placed on each boy's head a hat from the box and asked them to name the color of the hat they were wearing. Although all three responded to the question, only Adam knew the color of his hat. And now so do you.
  8. The Donny Hall puzzle

    Assuming "first" means lowest-numbered,
  9. Looks like Now I can get my life back. Nice puzzle.
  10. Celebrity Interview

    Nope. He is a "real" Bill, though. Just a little older than Clinton. Keep in mind that Picket's post is on the right track.
  11. Monty Hall Puzzle

    You can use the Search feature here to see whether a puzzle might have been already posted. Mouse over Activity tab and click on Search. A version of Monty Hall has in fact been posted here, although with enough different terminology it's hard to find. Either way, a member might know of a previous post and simply direct discussion to it. Regarding usefulness, puzzles are usually posted without the solution. This permits members to post their responses to your puzzle. When you feel it has been solved you can click the check mark (upper left corner of their post) to so indicate. If it's not solved after some time has passed you might want to post a clue (putting the clue into a spoiler.) You can put anything you like into a spoiler so it's not visible unless a member chooses to see it. Simply highlight the part of your post to be hidden and click on the eye icon and then submit your post.
  12. Monty Hall Puzzle

    Hi. That's a standard puzzle and you gave what I think is the best short answer
  13. Fun with digital sums

    Inspired by FUZZY's recent puzzle Suppose abcd is the normal decimal representation of a number: abcd = (1000a)+(100b)+(10c)+c. The digital sum of a number is defined as a+b+c+d. Are there numbers for which the product of its digital sum and its reversal is the original number? For example, the digital sum of 12345 is 15. Its reversal is 51. 15x51 is 765, 12345 is not equal ti 765, So 12345 is not a solution. Hint: 81 is a solution, as is 1. Are there others?
  14. Clarification? Each variable {A B C D E F G H I} can be used only once. I now assume, but it's not clear, that each operator {+ - x / ^ 10A+B]} can be used only once, making (9!)(6!) cases. I started allowing any operator to be used in each white triangle.
  15. Mega Einstein Riddle

    Post away (spoilered) then ... Good job.
  16. Area of a rhombus or kite

    I spent way too much time trying to figure out the calculus ban. Like there a catch and it should be obvious at some point. If there was a catch I didn't see it.
  17. Celebrity Interview

    Not bad. Wrong Bill, though. Who Bill is comes from somehow decoding the message.
  18. Integer equation?

    Here's an equation that's easy to analyze with a little insight. It's not original with me, I ran across it yesterday. (I'll provide attribution after it's solved.) x3 - y3 = 217 Does this equation have integer solutions (pairs of {x, y} integers)? If not, prove there are none; if so, find as many as you can.
  19. Mega Einstein Riddle

    Since there are active solvers, you may want to hold off with the solution. It's your call, of course. Another approach would be to drop a clue now and then (in a spoiler.) It's really a great puzzle, and it would be a notable accomplishment to be the first solver.
  20. The eldest son

    With a nod to jasen's recent and interesting puzzle, A traveler happened upon a village of huts, laid out as the circles in the picture below. The village's mayor explained to the traveler that the family living in each of the huts had an eldest son whose age was unique within the village. (No two eldest sons had the same age.) How interesting, replied the traveler. Tell me this: of all the male children here, what is the age of the very oldest? The mayor thought for a moment and replied, well I guess I could tell you that none of them are yet of voting age (21), and I guess you might be interested to hear that there are no gaps in their collective ages. But all of that wouldn't be enough information. I think it would be better for you to just knock on all the doors and ask. I don't have time for that, replied the traveler, and I'm really not that interested. Well, here's an interesting thing about our village, replied the mayor. You may have noticed, our huts are laid out so that many rows of 3, 4, or 5 huts cut across the entire village. Just ask at the huts along any of those rows. Add the ages that you hear, and divide the sum by two. That way you will learn the age of the oldest son in the village. And now, without knocking on any doors, you can learn it too.
  21. The eldest son

    The huts and their ages
  22. The eldest son

    @FUZZY Thalia is correct. My description of the sum is ambiguous.
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