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Given that (x, y) = (x+2y)/k if x = −2,1 and y = 3,4, is a joint probability distribution function for the random variables X and Y. Find: a. The value of K b. The marginal function of x c. The marginal function of y. d. (f(xly = 4)

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To find the value of K, we can use one of the given pairs of (x, y) values.

Given x = -2 and y = 3, we can substitute these values into the equation:

(x, y) = (x + 2y) / K

(-2, 3) = (-2 + 2(3)) / K

(-2, 3) = (-2 + 6) / K

(-2, 3) = 4 / K

To find K, we can rearrange the equation:

4 = (-2, 3) * K

K = 4 / (-2, 3)

Therefore, the value of K is -2/3.

b. The marginal function of x:

To find the marginal function of x, we need to sum the joint probabilities over all possible y values for each x value.

For x = -2:

f(-2) = f(-2, 3) + f(-2, 4)

For x = 1:

f(1) = f(1, 3) + f(1, 4)

c. The marginal function of y:

To find the marginal function of y, we need to sum the joint probabilities over all possible x values for each y value.

For y = 3:

f(3) = f(-2, 3) + f(1, 3)

For y = 4:

f(4) = f(-2, 4) + f(1, 4)

d. To find f(x|y = 4), we can use the joint probability distribution function:

f(x|y = 4) = f(x, y) / f(y = 4)

We can substitute the values into the equation and calculate the probabilities based on the given joint probability distribution function.

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