An urn holds 4 red, 3 blue, and 2 green marbles. Three marbles are selected, altogether, without replacement. Let Y be the number of red marbles obtained. What is the expectation of Y?

An urn contains 15 balls marked LOSE and 3 balls marked WIN. Suppose that Chuck and Delilia take turns selecting one ball from the urn, without replacement, where Vhuck makes the first selection. The individual that draws the third WIN ball wins the game. It does not matter who selected the first two.  Show that the probability Chuck wins the game on his third selection is equal to 1/136.

X 4. A bag of fast-food sandwiches contains two hamburgers, four cheeseburgers, and three chicken burgers. If Wyatt ordered a cheeseburger and a chicken burger, what is the probability that a) the first sandwich selected will be one of his choices? b) neither of the first two sandwiches will be among Wyatt's choices?

Mason drives to school for his class on Monday, Wednesday and Friday. He prefers to park in Parking Lot A because it is next to his classroom building, but he is not always able to find a spot there. If it's sunny the probability that he finds a spot is 0.72 but if it's raining more people drive, so the probability that he finds a spot is only 0.44. Whether he finds a spot in Lot A is independent from one day to the next. (a) On a sunny day, what is the probability that Mason does not find a spot in Lot A?   (b) In a week that is sunny on Monday and Friday and raining on Wednesday, what is the probability that Mason does not find a spot in Lot A on any of the three days? (Round your answer to four decimal places.)   (c) In a week that is sunny on Monday and Friday and raining on Wednesday, what is the probability that Mason finds a spot in Lot A on at least one of the three days? (Round your answer to four decimal places.)