A fitness center is interested in finding a 90% confidence interval for the mean number of days per week that Americans who are members of a fitness club go to their fitness center. Records of 268 members were looked at and their mean number of visits per week was 2.1 and the standard deviation was 1.8. Round answers to 3 decimal places where possible. a. To compute the confidence interval use a ? 0 distribution. b. With 90% confidence the population mean number of visits per week is between and visits. c. If many groups of 268 randomly selected members are studied, then a different confidence interval would be produced from each group. About percent of these confidence intervals will contain the true population mean number of visits per week and about percent will not contain the true population mean number of visits per week

Tina catches a 14-pound bass.  She does not know the population mean or standard deviation.  So she takes a sample of five friends and they say the last bass they caught was 9, 12, 13, 10, and 10 pounds.  Find the t and calculate a 95% (α = .05) confidence interval.

A fitness center is interested in finding a 90% confidence interval for the mean number of days per week that Americans who are members of a fitness club go to their fitness center. Records of 249 members were looked at and their mean number of visits per week was 2.2 and the standard deviation was 2.7. Round answers to 3 decimal places where possible. a. To compute the confidence interval use a ? distribution. b. With 90% confidence the population mean number of visits per week is between and visits. c. If many groups of 249 randomly selected members are studied, then a different confidence percent of these confidence interval would be produced from each group. About intervals will contain the true population mean number of visits per week and about percent will not contain the true population mean number of visits per week.

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A professor was curious about her students' grade point averages. She took a random sample of 15 students and found a mean GPA of 3.01 with a standard deviation of 0.534. Which of the following formulas gives a 99% confidence interval for the mean GPA of the professor's students?

Please help with 6 a-b

A random sample of 64 shoppers showed that they spend an average of $27.31 per visit at the Sunday Mornings Bookstore. The standard deviation of the population is $2.14. Find the 90% confidence interval of the true mean. Please include all work showing how you found your answer.

Researchers studied the mean egg length (in millimeters) for a bird population. After taking a random sample of eggs, they obtained a 95% confidence interval of (45,60). What is the value of the margin of error? Choose the correct answer below. A. 15 mm B. 52.5 mm O c. 7.5 mm O D. 1.96

A fitness center is interested in finding a 90% confidence interval for the mean number of days per week that Americans who are members of a fitness club go to their fitness center. Records of 228 members were looked at and their mean number of visits per week was 3.1 and the standard deviation was 2.8. Round answers to 3 decimal places where possible. a. To compute the confidence interval use a ?    distribution. b. With 90% confidence the population mean number of visits per week is between ?  and ?   visits. c. If many groups of 228 randomly selected members are studied, then a different confidence interval would be produced from each group. About ? percent of these confidence intervals will contain the true population mean number of visits per week and about ? percent will not contain the true population mean number of visits per week.

The mayor is interested in finding a 95% confidence interval for the mean number of pounds of trash per person per week that is generated in the city. The study included 249 residents whose mean number of pounds of trash generated per person per week was 34.8 pounds and the standard deviation was 7.2 pounds. Round answers to 3 decimal places where possible. b. With 95% confidence the population mean number of pounds per person per week is between   ?  and   ?  pounds. c. If many groups of 249 randomly selected members are studied, then a different confidence interval would be produced from each group. About        ?  percent of these confidence intervals will contain the true population mean number of pounds of trash generated per person per week and about    ?   percent will not contain the true population mean number of pounds of trash generated per person per week.