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    I'm stuck on this question for normal distribution, if anyone can help me that would be great.

    If X is a normally distributed variable with a mean of 24 and standard deviation of 2. Find:

    (a) p(X>28 | X ≥ 26)
    answer: 0.1434

    (b) p(26 < X < 28 | X ≥ 27)
    answer: 0.6595

    thank you so much!
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    (Original post by need_math)
    I'm stuck on this question for normal distribution, if anyone can help me that would be great.

    If X is a normally distributed variable with a mean of 24 and standard deviation of 2. Find:

    (a) p(X>28 | X ≥ 26)
    answer: 0.1434

    (b) p(26 < X < 28 | X ≥ 27)
    answer: 0.6595

    thank you so much!
    Ok
    Do you know how to convert to the standard normal? X to Z?
    Do you know the P(A|B) from the probability section? (A given B)
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    (Original post by m4ths/maths247)
    Ok
    Do you know how to convert to the standard normal? X to Z?
    Do you know the P(A|B) from the probability section? (A given B)
    I know how to do those 2 things but I don't know how to use it in this question
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    (Original post by need_math)
    I know how to do those 2 things but I don't know how to use it in this question
    OK find the P(X>28), write it down.
    find P(X>26), write it down.

    We can go from there.
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    (Original post by m4ths/maths247)
    OK find the P(X>28), write it down.
    find P(X>26), write it down.

    We can go from there.
    p(X>28) = 0.0228

    P(X>26) = 0.1587
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    (Original post by need_math)
    p(X>28) = 0.0228

    P(X>26) = 0.1587
    Ok, now apply P(A|B)
    (This one just requires a bit of common sense)
 
 
 
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