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Homework Help: T distribution?

  1. Oct 20, 2008 #1
    t distribution??

    1. The problem statement, all variables and given/known data
    If U and V are independent, U being distributed N(3,16) and V being distributed as chi-square on 9 degrees of freedom, find

    P(U-3 < 4.33 sqrtV).


    2. Relevant equations



    3. The attempt at a solution
    Well I don't even know where to start!! Does U-3 suggest the mean is 0? Is the whole distribution of U shifted left by 3? Does that give a t distribution?
    I am not asking for the answer but some direction would be appreciated, I just can't seem to understand this at all.
     
  2. jcsd
  3. Oct 20, 2008 #2

    EnumaElish

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    Re: t distribution??

    U-3 is distributed N(0,16).
     
  4. Oct 21, 2008 #3
    Re: t distribution??

    Ok, I understand this and also can reason that the probability would be very high, just by thinking of the graphs of the distributions, however I am still at a loss as to how to compute the probability. I use R to do the calculations, is it some kind of t test or do I put in the distributions and their parameters and just use R to calculate the probability, if so... is the R code just the same as in the question, that is, P(U-3 < 4.33 sqrtV)
     
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