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    The random variable x has a normal distribution. The mean μ (where μ>0) and the variance 1/4μ^2.

    (a) Find p(X>1.5μ)

    I am having trouble with this question so far I have got...

    P(z>2/μ)
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    anyone?
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    (Original post by Butterflyshy)
    The random variable x has a normal distribution. The mean μ (where μ>0) and the variance 1/4μ^2.

    (a) Find p(X>1.5μ)

    I am having trouble with this question so far I have got...

    P(z>2/μ)
    You divided by the variance, rather than the s.d.
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    (Original post by ghostwalker)
    You divided by the variance, rather than the s.d.
    I now get p(z>1), 1-p(z<1) which is 1-0.8413 which is 0.1587 which is the answer. Thanks for your help
 
 
 
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Updated: November 11, 2017
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