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    Four letters are picked at random from the word THURSDAY. What is theprobability that there is at least one vowel among the letters?

    (a)11/14(b)4/7(c)3/14(d)1/15

    I'm just a bit confused about what to do.
    I know the total number of possibilities is 8C4 =70 but I don't know where to go from there.
    Help is appreciated, thanks in advance
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    (Original post by jamesthelam)
    Four letters are picked at random from the word THURSDAY. What is theprobability that there is at least one vowel among the letters?

    (a)11/14(b)4/7(c)3/14(d)1/15

    I'm just a bit confused about what to do.
    I know the total number of possibilities is 8C4 =70 but I don't know where to go from there.
    Help is appreciated, thanks in advance
    Let v be the number of vowels picked.
    \mathbb{P}(v \geq 1) = 1- \mathbb{P}(v=0).
    Now consider the ways one can pick no vowels at all.
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    (Original post by joostan)
    Let v be the number of vowels picked.
    \mathbb{P}(v \geq 1) = 1- \mathbb{P}(v=0).
    Now consider the ways one can pick no vowels at all.
    Thanks, now that I think about it, it's obvious
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    (Original post by jamesthelam)
    Thanks, now that I think about it, it's obvious
    It crops up fairly frequently -something to watch out for.
 
 
 
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