Hip surgery: In a sample of 124 hip surgeries of a certain type, the average surgery time was 137.1 minutes, with a standard deviation of 22.7 minutes. Part: 0/2 Part 1 of 2 Construct a 99.9% confidence interval for the mean surgery time for this procedure. Round the answers to one decimal place. A 99.9% confidence interval for the mean surgery time for this procedure is <μ< Part: 1 / 2 Part 2 of 2 If a 98% confidence interval were constructed with these data, would it be wider or narrower than the interval constructed in part (a)? Explain. The new confidence interval would be (Choose one) than the interval constructed in part (a). X X

In a test of the effectiveness of garlic for lowering cholesterol, 48 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes (before - after) in their levels of LDL cholesterol (in mg/dL) have a mean of 5.5 and a standard deviation of 19.8. Construct a 99% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL cholesterol? Click here to view at distribution table. Click here to view page 1 of the standard normal distribution table, Click here to view page 2 of the standard normal distribution table. What is the confidence interval estimate of the population mean u? O mg/dL < µ

In a test of the effectiveness of garlic for lowering cholesterol, 47 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes (before - after) in their levels of LDL cholesterol (in mg/dL) have a mean of 3.7 and a standard deviation of 18.2. Construct a 90% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL cholesterol? Click here to view a t distribution table. Click here to view page 1 of the standard normal distribution table. Click here to view page 2 of the standard normal distribution table. What is the confidence interval estimate of the population mean p? Question Viewer mg/dL < p< mg/dL (Round to two decimal places as needed.) What does the confidence interval suggest about the effectiveness of the treatment? O A. The confidence interval limits do not…

A small university is trying to monitor its electricity usage. For a random sample of 30 weekend days (Saturdays and Sundays), the student center used an average of 94.26 kilowatt hours (kWh) with standard deviation 43.29. For a random sample of 60 weekdays, (Monday - Friday), the student center used an average of 112.63 kWh with standard deviation 32.07. Construct a 95% confidence interval for the difference in mean electricity use at the student center between weekdays and weekend days. Use two decimal places in your margin of error. -6.80 to 43.54 kWh -4.61 to 41.35 kWh -3.38 to 40.51 kWh 0.12 to 36.62 kWh

For a random sample of 64 overweight men, the mean of the number of pounds that they were overweight was 30. The standard deviation of the population is 4.2 pounds. (a) Find the best point estimate for the average number of excess pounds for all overweight men. (b) Construct a 95% confidence interval of the mean of these pounds.

In a test of the effectiveness of garlic for lowering cholesterol, 49 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes (before- after) in their levels of LDL cholesterol (in mg/dL) have a mean of 3.1 and a standard deviation of 15.8. Construct a 95% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL cholesterol? Click here to view a t distribution table. Click here to view page 1 of the standard normal distribution table. Click here to view page 2 of the standard normal distribution table. What is the confidence interval estimate of the population mean µ? mg/dL mg/dL<µ< (Round to two decimal places as needed.) What does the confidence interval suggest about the effectiveness of the treatment? O A. The confidence interval limits contain 0, suggesting that the…

Multi-sensor data loggers were attached to free-ranging American alligators in a study conducted by Y. Watanabe for the article “Behavior of American Alligators Monitored by Multi-Sensor Data Loggers”. The margin of error for a sample of 68 dives was 31.2 seconds. Assume the population standard deviation is 100 seconds. If for the next study, a confidence interval for μ is to have a margin of error of 25 seconds and a confidence level of 99%, determine the required sample size. (Round up to the nearest whole number.)