4. Suppose X and Y are two random variables with means ji and 42, respectively. (a)...

Question

Question

4. Suppose X and Y are two random variables with means ji and 42, respectively. (a) Find E(-X). (b) Find EaX + bY + c), where

math Statistics-And-Probability

Answer 1

Answer #1

(a) El-X) = -E(X) = -4

(b) EaX + bY + c) = a(X) +bE(Y) +c= api + buz to

(c) Var(ay) = E|(ay) - [E(ay) ; By definition of variance

=a^2E[Y^2]-a^2[E(Y]^2

= a* [E(Y!) - [E(Y)

= a Var(Y)

Answer 2

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