TOPIC: Linearity of expectations QUESTION: The random variable X is known to satisfy E[X] = 2...

Question

Question

TOPIC: Linearity of expectations

QUESTION: The random variable X is known to satisfy E[X] = 2 and E[X2] = 7. Find the expected value of 8−X and of (X−3)(X+3).

a) E[8−X]=

b) E[(X−3)(X+3)]=

math Statistics-And-Probability

Answer 1

Answer #1

Page No. Sol let the given __E(X)=2 values and E(X) = 7 Now a) EC 8-) by the Deo peeties of expectation E ax +b) = E(X) + b

Answer 2

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