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Thread: P(letter chosen Is I)

  1. #1
    Super Member harpazo's Avatar
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    P(letter chosen Is I)

    Each of the letters of the word MISSISSIPPI are written on separate pieces of paper that are then folded, put in a hat, and mixed thoroughly.One piece of paper is chosen (without looking) from the hat. What is the probability it is an I?

    Solution:

    There are 11 letters in the given word. The letter I appears 4 times.

    P(letter chosen is I) = 4/11

    Is this right?
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  2. #2
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    Re: P(letter chosen Is I)

    Quote Originally Posted by harpazo View Post
    Each of the letters of the word MISSISSIPPI are written on separate pieces of paper that are then folded, put in a hat, and mixed thoroughly.One piece of paper is chosen (without looking) from the hat. What is the probability it is an I?

    Solution:

    There are 11 letters in the given word. The letter I appears 4 times.

    P(letter chosen is I) = 4/11

    Is this right?
    Correct
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  3. #3
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    Re: P(letter chosen Is I)

    Yes, the probability of an "I" is 4/11. There are also 4 "S"s, 2 "P"s, and 1 "M". The probability of "S" is 4/11, the probability of a "P" is 2/11, and the probability of M is 1/11. Precisely because we have accounted for all letters, the sum of those probabilities is 4/11+ 4/11+ 2/11+ 1/11= (4+ 4+ 2+ 1)/11= 11/11= 1 as it should be.
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  4. #4
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    Re: P(letter chosen Is I)

    ...from a frequentist point of view.
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    Re: P(letter chosen Is I)

    Quote Originally Posted by TKHunny View Post
    ...from a frequentist point of view.
    f: 1/11
    r: 1/11
    e: 2/11
    q: 1/11
    u: 1/11
    n: 1/11
    t: 2/11
    i: 1/11
    s: 1/11

    ...do you finally understand, TK?
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  6. #6
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    Re: P(letter chosen Is I)

    Quote Originally Posted by DenisB View Post
    f: 1/11
    r: 1/11
    e: 2/11
    q: 1/11
    u: 1/11
    n: 1/11
    t: 2/11
    i: 1/11
    s: 1/11

    ...do you finally understand, TK?
    ?? The other point of view is this: Once you have chosen a letter, it is either an "I" or it isn't. There is no longer any distribution about it.

    This is what patients want to know about surgery survival rates. Patients are not interested in the actual survival rate - even if its 99%! The patient wants to know if he/she will survive -- Will I be in the 1% who don't make it?

    This is the WHOLE problem with the vaccination debate. The doctors are all saying, "It's safe and effective." In my view, this is excessively simplistic. What they MEAN is that the SOCIETAL benefits FAR outweigh the SOCIETAL risks. When you're looking at 60 million patients, killing only 1 of them is pretty good - from a SOCIETAL point of view. The mother of that one, however, is not comforted by the societal point of view.
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  7. #7
    Super Member harpazo's Avatar
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    Re: P(letter chosen Is I)

    Quote Originally Posted by HallsofIvy View Post
    Yes, the probability of an "I" is 4/11. There are also 4 "S"s, 2 "P"s, and 1 "M". The probability of "S" is 4/11, the probability of a "P" is 2/11, and the probability of M is 1/11. Precisely because we have accounted for all letters, the sum of those probabilities is 4/11+ 4/11+ 2/11+ 1/11= (4+ 4+ 2+ 1)/11= 11/11= 1 as it should be.
    This is a good breakdown of the question. Good data for my notes.
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