An entrepreneur is considering the purchase of a coin-operated laundry

1.An entrepreneur is considering the purchase of a coin-operated laundry. The current owner claims that over the past five years, the mean daily revenue was $675 with a population standard deviation of $75. A sample of 30 days reveals a daily mean revenue of $625. If you were to test the null hypothesis that the daily mean revenue was $675 and decide not to reject the null hypothesis, what can you conclude? 选项： A、There is not enough evidence to conclude that the daily mean revenue was $675. B、There is not enough evidence to conclude that the daily mean revenue was not $675. C、There is enough evidence to conclude that the daily mean revenue was $675. D、There is enough evidence to conclude that the daily mean revenue was not $675.

2. An entrepreneur is considering the purchase of a coin-operated laundry. The current owner claims that over the past five years, the mean daily revenue was $675 with a population standard deviation of $75. A sample of 30 days reveals a daily mean revenue of $625. If you were to test the null hypothesis that the daily mean revenue was $675, which test would you use? 选项： A、Z test of a population mean B、Z test of a population proportion C、 t test of population mean D、t test of a population proportion

3. An entrepreneur is considering the purchase of a coin-operated laundry. The current owner claims that over the past five years, the mean daily revenue was $675 with a population standard deviation of $75. A sample of 30 days reveals a daily mean revenue of $625. If you were to test the null hypothesis that the daily mean revenue was $675, which test would you use? A: Z test of a population mean B: Z test of a population proportion C: t test of population mean D: t test of a population proportion

4.A manager of the credit department for an oil company would like to determine whether the mean monthly balance of credit card holders is equal to $75. An auditor selects a random sample of 100 accounts and finds that the mean owed is $83.40 with a sample standard deviation of $23.65. If you wanted to test whether the mean balance is different from $75 and decided to reject the null hypothesis, what conclusion could you reach?选项： A:There is not evidence that the mean balance is $75.; B: There is not evidence that the mean balance is not $75.; C:There is evidence that the mean balance is $75.; D:There is evidence that the mean balance is not $75.

5.A manager of the credit department for an oil company would like to determine whether the mean monthly balance of credit card holders is equal to $75. An auditor selects a random sample of 100 accounts and finds that the mean owed is $83.40 with a sample standard deviation of $23.65. If you wanted to test whether the mean balance is different from $75 and decided to reject the null hypothesis, what conclusion could you reach? 选项： A、There is not evidence that the mean balance is $75. B、 There is not evidence that the mean balance is not $75. C、There is evidence that the mean balance is $75. D、There is evidence that the mean balance is not $75.

6.An analyst is investigating a stock index and gathered the following information:（）选项： A、Mean total revenue for all companies in the index B、$1.8 million C、Standard deviation of total revenue for all companies in the index D、$ 2.4 million

7.The owner of a local nightclub has recently surveyed a random sample of n = 250 customers of the club. She would now like to determine whether or not the mean age of her customers is greater than 30. If so, she plans to alter the entertainment to appeal to an older crowd. If not, no entertainment changes will be made. Suppose she found that the sample mean was 30.45 years and the sample standard deviation was 5 years. If she wants to have a level of significance at 0.01 what conclusion can she make 选项： A、There is not sufficient evidence that the mean age of her customers is greater than 30. B、There is sufficient evidence that the mean age of her customers is greater than 30. C、There is not sufficient evidence that the mean age of her customers is not greater than 30. D、There is sufficient evidence that the mean age of her customers is not greater than 30.

8.Which of the following would be an appropriate null hypothesis? 选项： A、 The mean of a population is equal to 55. B、The mean of a sample is equal to 55. C、 The mean of a population is greater than 55. D、 The mean of a population is less than 55.

9.The mean annual incomes of certified welders are normally distributed with the mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. A sample of 100 welders is taken and the mean annual income of the sample is $50,350. If the level of significance is 0.10, what conclusion should be drawn? 选项： A:

Do not reject the null hypothesis as the test statistic is less than the critical value of t.

B:

Reject the null hypothesis as the test statistic is greater than the critical value of z.

C:

Do not reject the null hypothesis as the test statistic is less than the critical value of z.

D:

Reject the null hypothesis as the test statistic is greater than the critical value of t.

10.Which of the following would be an appropriate null hypothesis?_ 选项： A、The mean of a population is equal to 78 B、The mean of a sample is equal to 78. C、The mean of a population is greater than 78. D、Only (a) and (c) are true.

11.Which of the following would be an appropriate null hypothesis? 选项： A、The mean of a population is equal to 55. B、The mean of a sample is equal to 55. C、The mean of a population is greater than 55. D、Only (A) and (C) are true.

12.A researcher is interested in testing to determine if the mean of population one is greater than the mean of population two. The null hypothesis is that there is no difference in the population means (i.e. the difference is zero). The alternative hypothesis is that there is a difference (i.e. the difference is not equal to zero). He randomly selects a sample of 9 items from population one resulting in a mean of 14.3 and a standard deviation of 3.4. He randomly selects a sample of 14 items from population two resulting in a mean of 11.8 and a standard deviation 2.9. He is using an alpha value of .10 to conduct this test. Assuming that the populations are normally distributed, the degrees of freedom for this problem are _______.选项： A:23 B:15 C:22 D:2

13.A researcher is interested in testing to determine if the mean of population one is greater than the mean of population two. The null hypothesis is that there is no difference in the population means (i.e. the difference is zero). The alternative hypothesis is that there is a difference (i.e. the difference is not equal to zero). He randomly selects a sample of 9 items from population one resulting in a mean of 14.3 and a standard deviation of 3.4. He randomly selects a sample of 14 items from population two resulting in a mean of 11.8 and a standard deviation 2.9. He is using an alpha value of .10 to conduct this test. Assuming that the populations are normally distributed, the degrees of freedom for this problem are _______.选项： A:23 B:22 C:21 D:2

14.What is the most important standard for an investor’s inspection on the hotel’s General Manager’s overall performance?选项： A:Average daily rate; B:Revenue per available room; C:Room occupancy percentage; D:Total amount of customers

15.A researcher is interested in testing to determine if the mean of population one is greater than the mean of population two. The null hypothesis is that there is no difference in the population means (i.e. the difference is zero). The alternative hypothesis is that there is a difference (i.e. the difference is not equal to zero). He randomly selects a sample of 9 items from population one resulting in a mean of 14.3 and a standard deviation of 3.4. He randomly selects a sample of 14 items from population two resulting in a mean of 11.8 and a standard deviation 2.9. He is using an alpha value of .10 to conduct this test. Assuming that the populations are normally distributed, the critical t-value from the table is _______.选项： A:1.323 B:1.721 C:1.717 D:1.321

16.An analyst performs a regression of a stock’s return on the overall market return using a sample of 2 years of monthly returns. He estimates the slope coefficient to be 0.55 with a standard deviation of 0.26. The analyst then performs a hypothesis test at a 5% level of significance to determine if the slope coefficient is significantly different from zero. Which of the following correctly describes the test statistic and result of this test? 选项： A: The test statistic is 2.12, and the null hypothesis is rejected to conclude that the slope coefficient is different from zero B: The test is 2.12, and the null hypothesis cannot be rejected to conclude that the slope coefficientIs different from zero C: The test is 0.47, and the null hypothesis cannot be rejected to conclude that the slope coefficient is different from zero D: The test is 0.47, and the null hypothesis is rejected to conclude that the slope coefficient is different from zero

17.Using the confidence interval when conducting a two-tail test for the population mean we do not reject the null hypothesis if the hypothesised value for µ:

18.A population distribution is normal with a mean of 18 and standard deviation of 4. A sample of 16 observations is selected and a sample mean computed. What is the probability that the sample mean is more than 18?? 0.0180.51.0

19.Which of the following would be an appropriate alternative hypothesis? 选项： A:The mean of a population is equal to 55.; B:The mean of a sample is equal to 55.; C:The mean of a population is greater than 55.; D:The mean of a sample is greater than 55.

20.Which of the following would be an appropriate alternative hypothesis?选项： A:The mean of a population is equal to 55.; B:The mean of a sample is equal to 55.; C:The mean of a population is greater than 55.; D:The mean of a sample is greater than 55.

21.Since a sample is a subset of the population, the sample mean（）.选项： A:is always smaller than the mean of the population; B:is always larger than the mean of the population; C:must be equal to the mean of the population; D:can be larger, smaller, or equal to the mean of the population

22.The Central Limit Theorem concerns the sampling distribution of the: 选项： A: sample standard deviation. B: population mean. C: sample mean.