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Let Xbe a random variable having expected value and variance 2. Find the expected value and variance ofY=X-.

Short Answer

Expert verified

Mean is 0, and variance is 1.

Step by step solution

01

Given information

Let X be a random variable having expected value and variance 2.

02

Calculation

Utilizing the linearity of expectation, we have that

EY-=1(E(Y)-E())=1(-)=0

And using the effects of the Variance (adding a constant accomplishes not change the variance and multiplying by a constant increase the variance by the square) we have that

VarY-=12Var(Y)=122=1

03

Final answer

The expected value and variance are0,1.

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