In a random sample of 6 mobile devices, the mean repair cost was $90.00 and the standard deviation was $14.00. Assume the population is normally distributed. Construct a 99% confidence interval for the population mean u. Find the margin of error. Round to the nearest hundredth as needed.

A nutritionist wants to determine how much time nationally people spend eating and drinking. Suppose for a random sample of 1088 people age 15 or​ older, the mean amount of time spent eating or drinking per day is 1.74 hours with a standard deviation of 0.54 hour. Determine and interpret a 95% confidence interval for the mean amount of time Americans age 15 or older spend eating and drinking each day.

You measure 34 turtles' weights, and find they have a mean weight of 65 ounces. Assume the population standard deviation is 5.2 ounces. Based on this, what is the maximal margin of error associated with a 95% confidence interval for the true population mean turtle weight.

Suppose that textbook weights are normally distributed. You measure 28 textbooks' weights, and find they have a mean weight of 73 ounces. Assume the population standard deviation is 10.9 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight. Round answers to 2 decimal places. Select an answer

You measure 37 textbooks' weights, and find they have a mean weight of 71 ounces. Assume the population standard deviation is 14.1 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight.

In a random sample of twelve ​people, the mean driving distance to work was 18.8 miles and the standard deviation was 4.9 miles. Assume the population is normally distributed and use the​ t-distribution to find the margin of error and construct a 90​% confidence interval for the population mean μ. Interpret the results.

You measure 27dogs' weights, and find they have a mean weight of 63 ounces. Assume the population standard deviation is 6.1 ounces. Based on this, what is the maximal margin of error associated with a 95% confidence interval for the true population mean dog weight.

Suppose that textbook weights are normally distributed. You measure 33 textbooks' weights, and find they have a mean weight of 61 ounces. Assume the population standard deviation is 13.2 ounces. Based on this, construct a 90% confidence interval for the true population mean textbook weight. Round answers to 2 decimal places.

Students preparing for comprehensive exams usually spend many hours studying. Suppose it is known that the time students spend studying for comprehensive exams has a distribution that is skewed heavily to the right with a mean of 41.3 hours and a standard deviation of 6.8 hours. If a simple random sample of 72 students is selected and the amount of time each spent studying for the comprehensive exam is determined. State and check the two assumptions.

A group of 49 randomly selected students has a mean age of 22.4 years. Assume the population standard deviation is 3.8. Construct a 90% confidence interval for the population mean. Include a statement interpreting your answer.