Question
Given independent random variables with means and standard deviations as shown, find the mean and standard...
|
Given independent random variables with means and standard deviations as shown, find the mean and standard deviation of each of these variables: |
||||||
|
Mean |
SD |
|||||
|---|---|---|---|---|---|---|
| a) 4X |
b) 4Y+3 | c) 2X+5Y |
X |
70 |
14 |
|
| d) 5X−4Y |
e) X1+X2 |
Y |
10 |
5 |
||
a) Find the mean and standard deviation for the random variable 4X.
E(4X)=_____________
SD(4X)=_______________
(Round to two decimal places as needed.)
b) Find the mean and standard deviation for the random variable 4Y+3.
E(4Y+3)= ________________
SD(4Y+3)= _____________________
(Round to two decimal places as needed.)
c) Find the mean and standard deviation for the random variable 2X+5Y.
E(2X+5Y)= ________________
SD(2X+5Y)= _________________
(Round to two decimal places as needed.)
d) Find the mean and standard deviation for the random variable 5X−4Y.
E(5X−4Y)= _________________
SD(5X−4Y)= _______________
(Round to two decimal places as needed.)
e) Find the mean and standard deviation for the random variable X1+X2.
EX1+X2=___________________
SDX1+X2=______________________
(Round to two decimal places as needed.)
Homework Answers
Answer #1
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