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Suppose random variables Y and XIY are distributed as below. What is E[X]? Show all steps of your work: 1 with probability 1/8_ 2Y with probability 3/4 , Y = XlY = 2 with probability 7/8 _ 3Y with probability 1/4 .

User Snarf
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Based on the given random variables and the probability values, the expected value of X is 5.375.

How to compute the expected value of X

Let's compute the expected value of X using the provided probabilities for Y and the relationships between Y and X:

When Y=1 with probability of 1/8, X=1.

When Y=2 with probability of 3/4, X=2Y=4.

When Y=X with probability of 7/8, X=Y=2.

When Y=3 with probability of 1/4, X=3Y=9.

Let's calculate E[X] step by step:

The expected value E[X] is given by the sum of each outcome multiplied by its respective probability:

The expected value E[X] is calculated as follows:

E[X] = (1 * 1/8) + (4 * 3/4) + (2 * 7/8) + (9 * 1/4)

E[X] = 1/8 + 3 + 14/8 + 9/4

E[X] = 1/8 + 3 + 7/4 + 9/4

E[X] = 1/8 + 12/4 + 9/4

E[X] = 1/8 + 21/4

E[X] = (1 + 42)/8

E[X] = 43/8

E[X] = 5.375

Therefore, the expected value of X is 5.375.

Suppose random variables Y and X are distributed as below. What is E[X]? Show all steps of your work:

1 with probability 1/8,

2Y with probability 3/4,

Y = X with probability 2 with probability 7/8,

3Y with probability 1/4.

User Gepcel
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