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aurao2003
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Homework Statement
Hi
I am trying to solve the d, e and f parts of this problem
The discrete random variable X has probability function
where k is a positive constant.
P(X = x) ={k(2 – x), x = 0, 1, 2,
k(x – 2), x = 3,
0, otherwise,
(a) Show that k = 0.25.
(b) Find E(X) and show that E(X 2) = 2.5.
(c) Find Var(3X – 2).
Two independent observations X1 and X2 are made of X.
(d) Show that P(X1 + X2 = 5) = 0.
(e) Find the complete probability function for X1 + X2.
(f) Find P(1.3 < X1 + X2 < 3.2).
Not sure how to begin. Please help. The exam is tomorrow.