Needing Help with Statistics Homework

Unit 6 - Section 9.2

Determine whether movement is true or false. To construct a confidence interval about the mean, the population from wt This stateme true. click the icon to view the table of areas under the t-distribution. -value such that the area in the right tal is 0.005 with 27 degrees of freedom. (Round to three decimal places as needer)" (b) Find the i-value such that the area in the right tail is 0.02 with 28 degrees of freedom. (Round to three decimal places as need (c) Find the f-value such that the area left of the t-value is 0.025 with 16 _ (Round to three decimal places as needed ) Find the critical t-value that corresponds to 989% confidence. Assum (Round to three decimal places as needed) Table of t-Distribution Areas Table VI 0.35 Q.05 0.025 Area in Right Tail Determine the point estimate of the pop and margin of error for the confidence interval. Lower bound is 21, upper bound is 25. The margin of error for the confidence interval Is 2 Click the icon to view the table of areas under the t-distribution, andard deviation, s, is found to be 4.7. (a) Construct a 95%% confidence interval about ; if the sample size, n, is 35. (Use ascending order. Round to two decimal places as needed.) (b) Construct a 959% confidence interval about us if the sample size. n, is 51. Lower bound : (Use ascending order. Round to two decimal places as needed.) How does increasing the sample size affect the margin of error, E? O A. The margin of error does not change. The margin of error decreases O C. The margin of error increases. (c) Construct a 99%% confidence interval about , if the sample size, n, is 35. (Use ascending order. Round to two decimal places as needed.) Compare the results to those obtained in part (a) How does increasing O C. The margin of error does not change. () if the sample size is 14, what conditions m O A. The sample data must come from a population that is normally distributed with no outliers O B. The sample size must be large and the sample should not have any outliers. O C. The sample must come from a population that is normally distributed and the sample size must be large. Table of t. Distribution Areas Table VI 0.25 0.20 0.15 Q,001 Area in Right Tail per bound: 38 8. Which of the following orked was lower counter paris (al through () below. by adults in this cour s between 37.2 hours and 38.8 hours. OA F O D. Flawed. This interpretation implies that the population mean varies rather than the interval en 37.2 hours and 38.8 hours. A Flawed This interpretation implies that the por mean varies rather than the interval. Flawed This interpretation makes an implication about individuals rather than the mean. O D . Flawed. This interpretation does not make it clear that the 95%% is the probability that the mean is within the interval , (c) 959% of adults in this country worked between 37.2 hours and 38.8 hours last week Oferect. This Interpretation is reasonable. O C. Flawed. This interpretation implies that the mean is only for last out within the interval. O D. Flawed. This interpretation makes an Implication about individuals rather than the mean. (di We are 95%% confident that the mean number of hours worked by adults in a particular area of this O A. Flawed. This interpretation implies that the population mean varies rather than the interva O C . Flewed. The interpretation should be about the mean number of hours worked by adults in the whole country. not about adults in the particular area. O D. Correct . This interpretation is reasonable . ed chan's drive-through has a lower bound of 170'5 seconds and an is tauraings A asks confidence interval that results from examin ng 686 customers in Choose the correct answer below. O A. One can be 959% confident that the mean drive-through service time of this fast food chain is 172.1 seconds. O B. There is a 95%% probability that the mean drive-through service time of this fast-food chain is between 17 O D. The mean drive-through service time of this fast-food chain is 172.1 seconds 959 of the time. points with 99%% confidence assuming s = 14.4 based on earlier studies? Suppose the doctor would be content with 95% confidence. How does the decrease in Click the icon to view a partial table of conical values . und up to the nearest subject. How does the decrease in confidence affect the sample size required? O A. Decreasing the confidence level decreases the sample size no O B. The sample size is the O C. Decreasing the confidence level increases the sample size needed. 3: Partial Critical Value Table Level of Confidence, Area in Each Tall, Critical Value, Za12 edom Increases. Choose the com O A. The t-distribut B. The t-distribu