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Joint Distribution

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TABLE 2.2 IS ATTACHED

Use the probability distribution given in Table 2.2 to compute (a) E(Y) and E(X); (b) Ï?2x and Ï?2Y; and (c) Ï?XY and corr(X,Y).

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First, we calculate E(Y) and E(X). Expectation equals the sum of each value of the outcome times the chance of that outcome occurring.

E(Y) = 0.22 X 0 + 0.78 X 1 = 0.78

E(X) = 0.3 X 0 + 0.7 X 1 = 0.7.

Next, variance = the sum of probability X (the state of x - the mean of x)^2

Var(Y) = ...

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Joint Distribution

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Answer: 2000 hours

6. The life, X in hundred of hours, of a certain battery has the following density function

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7. The waiting time, in hours, between successive speeders spotted by a radar unit is a continuous random variable with cumulative distribution

What is the expected or average time between successive speeders?

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9. The following represents the projection graph for a probability distribution f(x) of a random variable X.

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What is the expected value of X?

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Determine the expected life span for an electrical component.

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