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    for B(10,0.22)

    how would you work out P(X>=6)

    really stuck, thank you
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    (Original post by raiden95)
    for b(10,0.22)

    how would you work out p(x>=6)

    really stuck, thank you
    p(x>=6) = 1- p(x<=5)
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    (Original post by joostan)
    p(x>=6) = 1- p(x<=5)
    but 0.22 is not in the tables
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    (Original post by raiden95)
    but 0.22 is not in the tables
    1-P(x\leq 5)=1-P(x=0,1,2,3,5,) although this is long it does work I'm sure there's a faster method I'm missing.
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    Mean = 10 and S.D = 0.22

    P ( X >= 5 ) = P ( Z >= 5-10/0.22)

    therefore = P ( Z >= -0.23 )

    now you need to change that (-0.23)

    you do 1 - P ( Z <= 0.23) >>>0.23 in the table look for P which is 0.5910

    now do 1 - 0.5910 = 0.409 is the answer !


    Hope it is clear .
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    (Original post by charly2012)
    Mean = 10 and S.D = 0.22

    P ( X >= 5 ) = P ( Z >= 5-10/0.22)

    therefore = P ( Z >= -0.23 )

    now you need to change that (-0.23)

    you do 1 - P ( Z <= 0.23) >>>0.23 in the table look for P which is 0.5910

    now do 1 - 0.5910 = 0.409 is the answer !


    Hope it is clear .
    How did you come to the conclusion that mean = 10? n=10, n is not the mean. It's Binomial distribution, not normal distribution, those are binomial parameters, not normal parameters.
    If a random variable X follows a binomial distribution then X~B(n,p)
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    oh my bad . i thought it was normal distribution
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    (Original post by Robbie242)
    1-P(x\leq 5)=1-P(x=0,1,2,3,5,) although this is long it does work I'm sure there's a faster method I'm missing.
    I was thinking of this too, really was hoping there was an easier way or maybe its just a typical stupid textbook question lol thanks
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    (Original post by charly2012)
    oh my bad . i thought it was normal distribution
    i could actually use normal distribution by normal approximation, but since this is hypothesis testing it would take very long to test other values
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    (Original post by raiden95)
    I was thinking of this too, really was hoping there was an easier way or maybe its just a typical stupid textbook question lol thanks
    np and yeah its stupid, but I think this is the only route tbh, np
 
 
 
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