1. The distribution of heights for adult women in a certain population is approximately normal with mean 62 inches and standard deviation 2 inches. Which of the following represents the middle 60 percent of the heights? a) 60 and 64 b) 59 and 65 c) 59.5 and 64.5 d) 59.2 and 54.8 e) 60.3 and 63.7 RK M=62 0=4 interval=.6 1-16 2 P(x > Z) = P(x >Y = 23 =.2 2. The distribution of the amount of water used in a shower is approximately normal with mean 17 gallons and standard deviation 2 gallons. Which of the following is closest to the probability that no more than 14.5 gallons are used for any wash cycle? a).1056 b) .4568 c) .8536 d) .8944 e) .9734 a) z b) s c) o d) H en 3. The statistic x is used as an estimator for which of the following? 4. In a certain state, the proportion of the population with green eyes is 8% percent. A random sample of 500 people will be selected from the population. What is the mean of the sampling distribution of the sample proportion of people with green eyes for samples of size 500? a) .08 b) .01 c).92 d) 4.88 e) 40 enter return AC shift are missing eyes. Of the following, which is the least value for a sample size that will allow for 5. A sample of dolls will be selected from a large population in which 6 percent of the toys the sampling distribution of the sample proportion to be assumed approximately normal? a) 40 b) 119 167 d) 225 e) 311 6% 6. The city of Asheville estimates that 83 percent of all households recycle. Let p represent the population proportion of all households that recycle. For the sampling distribution of the sample proportion for samples of size 500,=.83. Which is the best interpretation of P=.83 PT Pr households who recycle is .83 a) For all samples of size 500, the standard deviation of all possible sample proportions of b) For a randomly selected household, the percentage of people who recycle in the household is .83. recycle is .83 For all samples of size 500, the mean of all possible sample proportions of households who d) For each sample of size 500, the proportion of households that recycle is .83 e) For a randomly selected household, the probability that they recycle is .83 7. The mean age of the employees at a company is 42.5 years, and the standard deviation is 8.4 years. A random sample of 16 employees will be selected. What is the mean and standard deviation of a 16 person sample? 42.5 16 42.5 16 years and the standard deviation is 8.4 years a) The mean is b) The mean is years and the standard deviation is .525 years c) The mean is 42.5 years and the standard deviation is 2.1 years d) The mean is 2.66 years and the standard deviation is 2.1 years e) The mean is 42.5 years and the standard deviation is 8.4 years 8. The distribution of the commute times for the employees at a large company has mean 31.3 minutes and standard deviation 7.9 minutes. A random sample of n employees will be selected and their commute times will be recorded. What is true about the sampling distribution of the sample mean as n decreases from 50 to 10? a) The mean increases, and the variance increases. The mean increases, and the variance decreases. c) The mean does not change,, and the variance decreases. d) The mean does not change, and the variance does not change. e) The mean does not change, and the variance increases. return 15. A random sample of size 36 is to be selected from a normal population having a mean of 70 and a variance of 25. What is the 85th percentile of the sampling distribution of the mean? a) 70.86 b) 69.14 c) 69.86 d) 70.14 95.91