Stats Problem about Expectations of Random Variables

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Homework Statement



Let X have mean u and variance s^2. Find the mean and the variance of Y=[(X-u)/s]

Homework Equations


The Mean is linear

The Attempt at a Solution


I thought to just plug in the mean of X anywhere i saw it in Y so mean of Y would be 0
and then for the variance I was kind of lost... Any suggestions?
 
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Remember

<br /> \begin{align*}<br /> E(aY+b) &amp;= aE(Y)+ b\\<br /> Var(aY) &amp; = a^2 Var(Y)<br /> \end{align*}<br />
 
Didn't know that second formula. Thanks for your help!
 
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