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# State whether the following is always true (T) or not always true (F) a)V (4X −...

State whether the following is always true (T) or not always true (F)
a)V (4X − 2Y ) = 16V (X) + 4V (Y ) + 8Cov(X, Y )

b)If X1, X2, ..., X100 are independent, normally distributed random variables, then the average X¯ = 1 100Σ 100 i=1Xi of these random variables is itself a random variable following a normal distribution.

c) If X and Y are random variables with a correlation of ρxy, Corr(2X, Y ) = 2ρxy

TOPIC: Variance ,covariance,Sampling distribution of sample average from a Normal distribution,Correlation coefficient between variables.  #### Earn Coins

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