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    Hey there, I am stuck on the following question, can you help me out please?
    Cheers

    Suppose a football player scores penalties with a probability of 2/3.
    What is the probability that they score exactly once if they take 5 penalties?
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    (Original post by dewitrydan)
    Hey there, I am stuck on the following question, can you help me out please?
    Cheers

    Suppose a football player scores penalties with a probability of 2/3.
    What is the probability that they score exactly once if they take 5 penalties?
    Do you know the binomial distribution?
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    No sorry, thats all the info I had on teh question
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    It's binomial with paremters x~b(n=1, p=2/3)
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    X~B(5, 2/3)

    P(x=1)

    Then use either the tables or the formula
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    Instead of thinking about it as a binomial distribution, you can do it more logically.

    If he only scores 1, then he either:

    scores the 1st and misses the others
    scores the 2nd and misses the others
    .
    .
    scores the 5th and misses the others

    What's the probability of each of these? (shortcut: they each have the same probability)
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    (Original post by Daniel Freedman)
    Instead of thinking about it as a binomial distribution, you can do it more logically.

    If he only scores 1, then he either:

    scores the 1st and misses the others
    scores the 2nd and misses the others
    .
    .
    scores the 5th and misses the others

    What's the probability of each of these? (shortcut: they each have the same probability)
    Okay, so they each have the same probability, do you then add the probabilities up?
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    Tree Diagram :P
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    (Original post by dewitrydan)
    Okay, so they each have the same probability, do you then add the probabilities up?
    Yes.
 
 
 
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