GB513 Unit 2 Quiz Latest 2017 (Score 100%)

QuestionQuestion 1 2 / 2 pointsA standard normal distribution has the following characteristics:1) The mean and the variance are both equal to 12) The mean and the variance are both equal to 03) The mean is equal to the variance4) The mean is equal to 0 and the variance is equal to 15) The mean is equal to the standard deviationQuestion 2 2 / 2 pointsThe total area underneath any normal curve is equal to:1) the mean2) one3) the variance4) the coefficient of variation5) the standard deviationQuestion 3 2 / 2 pointsKristen Ashford purchased the subscribers list for Wind Surfing magazine. She plans to survey a sample of the subscribers before using the list in her mail order business. She chooses the first 100 of the 5,000 names. Her sample is a:1) simple random sample2) stratified sample3) systematic sample4) convenience sample5) cluster sampleQuestion 4 2 / 2 pointsThe area to the right of the mean in any normal distribution is equal to:1) the mean2) 13) the variance4) 0.55) –0.5Question 5 2 / 2 pointsIf x is a normal random variable with mean 80 and standard deviation 5, the z-score for x = 89 is:1) 1.82) –1.83) 1.64) –1.65) 8.0Question 6 2 / 2 pointsWithin a range of z scores from –1 to +1, you can expect to find _______ percent of the values in a normal distribution.1) 952) 993) 684) 345) 100Question 7 2 / 2 pointsThe expected (mean) life of a particular type of light bulb is 1,000 hours with a standard deviation of 50 hours. The life of this bulb is normally distributed. What is the probability that a randomly selected bulb would last more than 1100 hours?1) 0.47722) 0.97723) 0.02284) 0.52285) 0.5513Question 8 2 / 2 pointsCompletion time (from start to finish) of a building remodeling project is normally distributed with a mean of 200 workdays and a standard deviation of 10 workdays. To be 99% sure that you will not be late in completing the project, you should request a completion time of _______ workdays.1) 2112) 2073) 2234) 2005) 250Question 9 2 / 2 pointsFinancial analyst Larry Potts needs a sample of 100 securities listed on either the New York Stock Exchange (NYSE) or the American Stock Exchange (AMEX). According to the Wall Street Journal's "Stock Market Data Bank," 2,531 NYSE securities and 746 AMEX securities were traded on the previous business day. Larry directs his staff to randomly select 77 NYSE and 23 AMEX securities. His sample is a:1) disproportionate systematic sample2) disproportionate stratified sample3) proportionate stratified sample4) proportionate systematic sample5) proportionate cluster samplingQuestion 10 2 / 2 pointsSuppose 40% of a student population works part time. If a random sample size of 300 students is drawn from the population, then the probability that 44% or fewer of the samples work part time is:1) 0.07932) 0.42073) 0.92074) 0.99005) 1.0000