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Approximately 14 percent of the population of Arizona is 65 years or older. A random sample of five persons from this population is taken. The probability that less than 2 of the 5 are 65 years or older is: Select one: a. 0.8533 b. 0.1467 c. 0.4704 d. 0.3829 e. None of these. Which of the following is a discrete random variable? Select one: a. The average daily consumption of water in a U.S. household. b. The weight of football players in the NFL. c. The number of three-point shots completed in a college basketball game. d. The time required to drive from Dallas to Denver. e. The average daily temperature in the world A box of chocolates contains 18 pieces, 10 of which have nuts while the remaining 8 do not. Four pieces are chosen at random. What is the probability that exactly 2 pieces have nuts? Select one: a. 0.412 b. 0.564 c. 0.681 d. 0.750 e. 0.833 A new car salesperson knows that he sells cars to one customer out of 20 who enter the showroom. The probability that he will sell a car to exactly two of the next three customers is: Select one: a. 0.9939 b. 0.0075 c. 0.0071 d. 0.0851 e. 0.1354 A box of chocolates contains 18 pieces, 10 of which have nuts while the remaining 8 do not. Four pieces are chosen at random. What is the probability that at least 3 pieces have nuts? Select one: a. 0.051 b. 0.118 c. 0.169 d. 0.242 e. 0.382 Which of the following statements are true? Select one: a. For the Poisson distribution = 3.2, the mean and standard deviation are both equal to 3.2. b. For the Poisson distribution = 3.2, the mean and variance are both equal to 3.2. c. For the Poisson distribution = 3.2, the mean is 3.2 and the standard deviation is 1.79. d. Both B and C are correct. e. All of these are correct. The variance of a binomial distribution for which n = 75 and p= 0.20 is: Select one: a. 375. b. 75. c. 15. d. 12. The expected value, E(x), of a binomial probability distribution is: Select one: a. n + b. n (1 - ) c. np d. n + -1 Which probability distribution is appropriate when sampling is performed without replacement from a relatively small population? Select one: a. Binomial distribution b. Poisson distribution c. Hypergeometric distribution d. Normal distribution e. Exponential distribution A local police station receives an average 8.1 emergency telephone calls per hour. These calls are Poisson distributed. The probability that the station will get five to seven calls in an hour is: Select one: a. 0.5924. b. 0.5617. c. 0.4383. d. 0.4076. e. 0.3451.