HW #8: Probability

An urn contains 10 marbles: 4 RED, 3 BLUE, 2 WHITE, and 1 GREEN We will make 5 draws from this urn, one at a time, without replacement. Find the probability that "the 5th draw is white". Find the probability that "the first draw is red" AND "the second draw is white" AND "the third draw is blue". Find the probability that "the first draw is green" OR "the second draw is green" OR "the third draw is green" OR "the fourth draw is green" OR "the fifth draw is green". Find the probability that "the first draw is red" OR "the second draw is red". Find the probability that "the first draw is blue" OR "the second draw is blue" OR "the third draw is blue".

2/10 24/720 5/10 2/3 1- (210/720)

In order to win a war, the general can opt to fight and win one large battle, or fight and win ALL of three small battles. The general believes the chance of winning the large battle to be 0.5. The general also believes the chance of winning any given small battle to be 0.8 and each outcome of any small battle is independent of the other small battles. Which option (1 large battle or 3 small battles) is best for the general?

3 small Battles, since 0.512 > 0.5

A survey of top executives revealed that 35% regularly read Time magazine, 20% read Newsweek and 40% read US News & World Report. 10% read both Time AND US News & World Report. What is the probability that a randomly picked top executive in the survey reads either Time OR US News & World Report regularly?

65%

Which of the following statements is correct regarding the probability of an event E:

P(E) + P(E') = 1, where E' is the complement of E

Since the sun must rise tomorrow, then the probability of the sun rising tomorrow is

no other answer is correct Other answers: - infinity - much larger than one - zero

Two events, A and B, are disjoint and each have a nonzero probability. If event A is known to occur, the probability of the occurrence of event B is

zero