Recent content by afireinside

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    Probability density expected values

    So are you saying the answer should be 9, and the answer sheet is wrong? Then what about E[x^2], is that 81 or is it 85.5 by doing a similar integral just with x^2 instead of x?
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    Calculating Marginal Density and Expectation of Project Cost

    Homework Statement Let the joint density of the material and labor cost of a project be modeled by fx,y(u,v) = 2v*e-v*(2+u) u,v ≥ 0 = 0 otherwise a) find marginal density of X and Y b) find E(Y)...
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    Probability density expected values

    Homework Statement Bearing capacity of soil varies between 6 and 15 kips/sq.ft. If probability density within this range is given as f(x)=1/2.7 * (1- x/15), 6 ≤ u ≤ 15 =0 otherwise Find E(X) and E(X^2) Homework Equations E(x) should be ∫x*f(x) dx...