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

x 0 1 2 3 4

px(x) 0.1 0.2 0.3 0.29 0.11

The probability that a particular customer buys an extended warranty given they purchase a camera is 0.60. Let Y denote the number of purchasers during this week who buy an extended warranty. (Give answers accurate to 3 decimal places.)

(a) What is P(X = 4, Y = 2)?

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.

(b) Determine the joint pmf of X and Y:

How to compute P(X=2 & Y=1) & P(X=3 & Y=2)??

Super needed!!! Thanks!!!