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Probability help please!

  1. Aug 29, 2011 #1
    So I took probability last year, and for one of my classes we have an optional refresher worksheet, but I cannot remember how to deal with random variables :(

    I don't need the answer -- just some guidance on what formulas to use please!

    x is a random variable with mean 5 and variance 12.

    y = 3 + 9x

    a) what is the expected valued of y?

    b) what is the variance and SD of y?

    c) is y normally distributed?

    thank you so much!!!
  2. jcsd
  3. Aug 29, 2011 #2

    I like Serena

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