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bonanova

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Everything posted by bonanova

  1. bonanova

    Nice one ... !
  2. bonanova

    Hi Noct, My comment was not meant to say your answer is wrong. I was commenting, rather, about the OP: First, I would say it's not a well posed problem. Consider the significant differences among these three statements. [1] Each year it continues to grow at the rate of double the previous years height. [2] Each year its height changes by a multiplicative factor equal in magnitude to two times the current height of the tree expressed in cm. [3] Each year its height increases by an amount equal to two times its current height. Statement [1] is from the OP and is not well posed. Statement [2] is well posed, and would be, to my thinking, what the OP tried to say. Statement [3] is well posed and leads to your answer. If you take the OP as a formula for calculating next year's growth rate from this year's height: [1] leaves you in the dark as to what units to use: cm, inches, feet, meters and furlongs all give different results. [2] works, but isn't what the OP says. [3] tells you how the height changes, but it isn't what the OP says; it doesn't address growth rate at all - rather a growth amount. Second, a growth rate most commonly refers to the derivative of height with respect to time, and it has the units of [length]/[time]. If [2] is what is meant, calling a factor a rate is incorrect; they have different dimensions. Rate is dimensionless. If [3] is what is meant, calling a height increase a rate is also incorrect. Summarizing, Rate = [length/time]; height and height increase = [length] and factor = [dimensionless]. To say Rate = 2 x Height creates a dimensionality error. To say Factor = 2 x Height also creates a dimensionality error. To say Height increase = 2 x Height is dimensionally correct, but the OP purports to specify a rate. So to my mind the OP does not say clearly how the tree grows. Regarding my comment about alternative, I'm simply saying that if you abandon the idea of calculating a growth rate [or factor or height increase] from the tree's current height, you're pretty much left with taking the OP to say that the height, itself, doubles each year.
  3. bonanova

    Using a knife to make four straight-line cuts, how many pieces can a single pancake be divided into? Generalize for N cuts.
  4. bonanova

    Since by definition a composite number is not a prime, and in particular neither 0 nor 1 are primes nor composites, I am interested to hear what the OP thinks the answer is.
  5. bonanova

    For more on that issue, read my rant about the abuse of ZERO here. This question is an example of confusing absence vis-a-vis presence in zero amount.
  6. I think I have it. Oops. Nope. My answer would make 4 -> 8. Still thinking.
  7. bonanova

    Good catch on the spelling errors. Here's a hint to finish the thing off.
  8. bonanova

    Here's another batch. 2008 NBA All Stars. Enjoy!
  9. bonanova

    The inference is not always true: 18/6 = 3 24/6 = 4
  10. bonanova

    This has been posted before, slightly modified. The answers are:
  11. bonanova

    Rat Stalls Arrest [and] Rug Sewers Averted: No Lambs Jeer Averting Kent Nine Overalls Kabob Entry Damn Tunic Gamy Ion And We Awed The Royal Conman Growth Hid Wad Adjoins KD [and] Seven Hats See Archaic Pelvis: Land Musk - Draw Hog Width Phoniest Outer Tooth - So Nook Japan Grave Mall Stamp - Man Lobs Jeer Selling Shellack - In Wiedo Malls
  12. This is good one ... let it ride for a while.
  13. I think these probabilities apply to a ruler with length 2, not length 3. Hint: Imagine the ruler begins in the center of a square.
  14. bonanova

    Nice going! That leaves just 6. The Evil Kilos - Behind Fetid Lasagna 8. Air Cabal - Faun Entertains Jaguar
  15. bonanova

    Great clues ... answer is imminent, I think.
  16. bonanova

    Are there three distinct digits in the original number? Or do we not need to know that?
  17. If you want to save some calculation time, note that V[removed] = V[cylinder] + 2xV[spherical cap] See what you get ...
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