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Let X denote the number of Canon SLR cameras sold during a particular week by a

ID: 3381929 • Letter: L

Question

Let X denote the number of Canon SLR cameras sold during a particular week by a certain store. The pmf of X is

Sixty percent of all customers who purchase these cameras also buy an extended warranty. Let Y denote the number of purchasers during this week who buy an extended warranty.

(a) What is P(X = 4, Y = 2)? [Hint: This probability equals

P(Y = 2|X = 4) · P(X = 4);

now think of the four purchases as four trials of a binomial experiment, with success on a trial corresponding to buying an extended warranty.] (Round your answer to four decimal places.)
P(X = 4, Y = 2) =  

(b) Calculate P(X = Y). (Round your answer to four decimal places.)
P(X = Y) =  

(c) Determine the joint pmf of X and Y.

(0.6)x(0.6)xy · pX(x)

(0.6)y(0.6)xy · pX(x)    

(0.6)y(0.4)xy · pX(x)

(0.6)x(0.4)xy · pX(x)
Determine the marginal pmf of Y. (Round your answers to four decimal places.)

x 0 1 2 3 4 pX(x)     0.1 0.2 0.3 0.25 0.15

Explanation / Answer

Let X denote the number of Canon SLR cameras sold during a particular week by a