5. Suppose that X and Y have the following joint probability distribution: f(x,y) x 2 4...

5. Suppose that X and Y have the following joint probability distribution:

f(x,y)		x
f(x,y)		2	4
y	1	0.10	0.15
	2	0.20	0.30
	3	0.10	0.15

Find the marginal distribution of X and Y.

Find the expected value of g(x,y) = xy2 or find E(xy2).

Find (x and (y.

Find Cov(x,y)

Find the correlations ρ(x,y)

3.

The length of life X, in days, of a heavily used electric motor has probability density function

Find the probability that the motor has at least 1/2 of a day, given that it has lasted 1/4 of a day.

Find the mean and the variance for X.

Expert Solution

orchestra answered 2 years ago

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