If X1, X2, and X3 are independent and have the means 4, 9, and 3 and the vaiance 3,7, and 5, find the mean and the variance of:
a. Y = 2X1 -3X2 +4X3
b. Z = X1 -2X2 -X3
If X1, X2, and X3 are independent and have the means 4, 9, and 3 and the vaiance 3,7, and 5, find the mean and the variance of:
a. Y = 2X1 -3X2 +4X3
b. Z = X1 -2X2 -X3
The mean is a linear application.
Therefore : and , E designing the mean.
From the definition,
But if X and Y are independent, then
I know this is probably a really stupid question, but do I just plug in the numbers given for mean and variance into the equation? Or what is my next step?
I know this is probably a really stupid question, but do I just plug in the numbers given for mean and variance into the equation? Or what is my next step?