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bonanova

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Everything posted by bonanova

  1. That's correct. It looks like you've read and understood the problem. Now read the solution and think about that for a bit. Take your example of 19 red and 1 black. Assign the black hat to one of the prisoners [to the first prisoner, the second, or one of the others] and work out the solution. If something specific doesn't seem to work, come back with a question. ------------------ You suggested: The OP requires each prisoner to name the color of his own hat. A prisoner who gives the color of another's hat risks his own execution. The solution guarantees 19 prisoners will survive. Would your solution do that?
  2. bonanova

    OK, I'll finish this one ...
  3. bonanova

    Ahem ... this is the Hall Monitor speaking ... PDA's r strikly agenst the rools here at brainded.
  4. bonanova

    [spoiler=no avatar left behind .. just the 73 ... take yer pick]Primal Heap Hamper Pail Hail Mapper Hipper Lama A Haler Pimp A Lip Hamper A Ham Ripple Impel A Harp Heal Map Rip Lame Hip Rap I Harm Apple
  5. bonanova

    Here's food for thought on puzzle solving: The OP does not say that the detective knew their occupations. Nor does the solution rest on his knowing them. The OP tells the solver what their jobs were. Take the conditions of the puzzle as given, and try to find an answer that does not contradict them. If it turns out then that the OP led you astray, have at it...! Kindly.
  6. bonanova

    No question - it's good. I like slickster's 1st answer, but I can't make it fit with I won’t be around forever you know - I may even start to stink. Or make anything else fit, for that matter. Nice one.
  7. bonanova

    WB, wow! Again I bow to the master. I gave it thought but had no clue. That's nothing; this type of riddle is not my forte. That you stumped Itachi-san is much higher praise. This part left me unable even to guess: Never have I been mistaken But when I’m right I’m in the wrong Good one! And nicely written. Kudos to Budouka! *quietly walks into the next room and slaps forehead*
  8. That's the right idea - losing speed increases your travel time more than gaining speed decreases it. Here's a driving example: Suppose you're traveling 60 mph on highway and hit 10 miles of 40 mph construction zone You spend 15 minutes there instead of 10, losing 5 minutes. Then suppose you try to get the time back by going the next 10 miles at 80 mph. Bad strategy, for two reasons. First, that next 10 miles still takes 7.5 minutes, saving not 5 minutes as you hoped, but only 2.5 minutes. Plus, you got a ticket. In the plane example, it's also useful simply to calculate travel time intervals: Suppose each leg of the trip is 600 miles, the air speed is 150 mph and the wind is 50 mph. At 100, 150 and 200 mph ground speeds, the one-way travel times are 6, 4 and 3 hours, respectively. Without wind, the total time is 4 + 4 = 8 hours. Avg speed = 1200/8 = 150 mph. With wind, it's 6 + 3 = 9 hours. Avg speed = 1200/9 = 133 1/3 mph. So the percentage change in speed or travel time is 12.5%
  9. bonanova

    I've calculated the other solutions, approximating the near polar region as a flat map. Referring to the diagram, where L = 500 km: The pilot starts out L+r km from the North Pole, then: flies north L km - to a distance r km from NP. flies west L km - in doing so, he circles the pole n times plus a degrees longitude. flies south L km. flies east L km - returning to starting point. West leg: [1] L = r[2npi + a] East leg: [2] L = a[r + L] Define f = r/L. then from [2] [3] a = 1/(1+f) Substitute [3] into [1] and simplify: [4] f2 + f - 1/(2npi) = 0 which solves to [5] f = [-1 + SQRT(1 + 2/npi)]/2 The starting distances from NP are given by 500 (1+f) km. Here are the values for n = 1, ..., 10 569.83 537.04 525.25 519.16 515.44 512.93 511.12 509.76 508.69 507.83 km from NP.
  10. bonanova

    Welcome to the Den Zelda! - bn
  11. bonanova

    I looked for such a reference, without finding one. I know I've heard it used that way, probably in an old gangster movie. But Googling reasonable phrases hasn't turned anything up. Thanks for being a good [and humorous] sport. - bn
  12. bonanova

    Are these supposed to rhyme?
  13. Nice breakdown. So ... in "rhythm" and related words, the consonants "r" and "th" partly obstruct the breath; "h" is silent; and "y" is left to provide the vowel sound.
  14. bonanova

    Me7o9, If you put your answer into a spoiler, it lets others have a shot at replying. Thanks. - bn
  15. I don't know what a pool boy's duties are, either. So say he doesn't check the water. Who would, then? Lifeguard, maybe.
  16. Hi bobbyb. Think a bit about the formulas you wrote down. Do they make sense to you? Do the units match? If you double your speed do you expect the time to double? If there were a 500mph headwind, what would happen during that leg of the flight? Maybe you just wrote them down in a hurry. If not, read up on the subject and then give it some more thought.
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