MULTIPLE CHOICE (1 point each). 1. Suppose that the random variable X has a binomial distribution and that the success probability, p, is greater than 0.5. The probability distribution of X is A) right skewed B) left skewed C) symmetric A bag contains 8 red marbles and 10 green marbles. Anne picks 3 marbles at random, with replacement, and observes the color of each marble. The number of green marbles, X, is a binomial random variable. If we let success correspond to getting a green marble, what is the success probability, p? What is the number of trials? A) p=l/3,n=3 B)p:l/10,n218 C)p:5/9,n:18 D)p=5/9,n=3 Suppose we toss a fair coin repeatedly. We continue to do this until a tail is observed. Let X be the number of tosses required. Then X has: A) a binomial distribution, with mean 0.5. B) a binomial distribution, with mean 2. C) a binomial distribution, with variance 0.707. D) None of the answer options is correct. For which of the following counts would a binomial probability model be reasonable? A) the number of phone calls received in a one-hour period B) the number of hearts in a hand of ve cards dealt from a standard deck of 52 cards that has been thoroughly shufed C) the number of sevens in a randomly selected set of ve digits from your table of random digits D) All of the answer options are correct. Which of the following statements is true about a binomial experiment? A) The number of trials can vary. B) There are only two possible outcomes: success and failure. C) The probability of success and failure can change from trial to trial. D) Each trial in the experiment may depend on previous trials. Three random variables X, Y, and Z are described below. In which of these situations the variable has either an exact binomial distribution or an approximate binomial distribution? I: A bag contains 4 blue marbles and 8 red marbles. Five marbles are drawn at random with replacement. The random variable X is the number of blue marbles drawn. II: A bag contains 4 blue marbles and 8 red marbles. Six marbles are drawn at random without replacement. The random variable Y is the number of blue marbles drawn. III: A bag contains 30 blue marbles and 38 red marbles. Three marbles are drawn at random without replacement. The random variable Z is the number of blue marbles drawn. A) I only B) 11 and III C) I, II, and III D) I and