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

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