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Statistics Riddle

Discussion in 'Off-Topic' started by Cpt. Cynical, Sep 29, 2006.

  1. Cpt. Cynical

    Cpt. Cynical Chieftain

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    My stats instructor gave the class an interesting statistical riddle today. Here's how it goes:

    Calculate:

    111,111,111 X 111,111,111

    How is the answer like the normal curve (standard normal distribution)?


    The answer, I think, is 12,345,678,987,654,321. How is that like the normal curve?

    Well, I can figure out that the number obviously looks "bell-shaped" in that it starts with 1 on the outside and ascends to 9 in the middle.

    Can you folks think of anything else? This is getting on my nerves, as if I am missing something obvious because I'm not savvy with statistics. :confused:
     
  2. brennan

    brennan Argumentative Brit

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    123...321 would just be a triangle

    1x1=1
    11x11=121
    111x111=12321
    1111x1111=1234321

    Pattern established. Not a bell curve though.:confused:
     
  3. Perfection

    Perfection The Great Head.

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    Brennan seems to be on the mark here.

    I'm curious as to the origin of this riddle.
     
  4. Brighteye

    Brighteye intuitively Bayesian

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    You could also say that as you multiply larger 1111 numbers a bar graph of the result approximates ever more closely to a triangle, just like larger ns give a mean that approximates more closely to the normal distribution.
    Yes, I know its tenuous.
     
  5. Perfection

    Perfection The Great Head.

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    I wonder how the digit pattern changes under different bases. Someone mak me some graphs! I'd do it now, but it's 3:00 AM.
     
  6. brennan

    brennan Argumentative Brit

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    Binary:

    1x1 = 1
    11x11 = 1001
    111x111 =110001
    1111x1111 = 11100001
    11111x11111 = (on my calculator it's E for error, but..) 1111000001
    111111x111111 = 1111110000001

    Odd pattern. Interesting though.
     
  7. Elrohir

    Elrohir RELATIONAL VALORIZATION

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    I think it's capital "E" for exponent.
     
  8. brennan

    brennan Argumentative Brit

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    Trust me man. I know what notation my scientific calculator uses for exponent. When all it does is say -E- it means the number is too big to show. (it doesn't show exponents in bases other than 10).
     
  9. Xenocrates

    Xenocrates Chieftain

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    Is it possible, stat fans, that the OP's answer
    should be interpreted 10^1, 10^2 etc?

    I know that also wouldn't resemble a normal distribution as the top should flatten off, but at least it's curved......

    Now this is driving me crazy too (a short drive Brennan ;) ), how much like a normal curve should this be exactly?
     
  10. nihilistic

    nihilistic Intergalatic Delivery Boy

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    Besies symmetry, it is not. That's the end.

    There is nothing obvious besides the stupidity of the question. Likewise this question also has nothing to do with statistics and everything to do with numerology.
     
  11. Red Stranger

    Red Stranger Chieftain

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    It's like statistics because in the end it's just numbers. Anyone can try to make sense of the numbers or try to find patterns in the numbers. But it's just an illusion.
     
  12. Perfection

    Perfection The Great Head.

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    Well, statistical ideas are very important in physics, and physics tends not to be an illusion. ;)

    Nice joke, though.
     

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