Suppose that a random sample of nineteen recently sold houses in a certain city has a...
Suppose that a random sample of fourteen recently sold houses in a certain city has a mean sales price of $275,000, with a standard deviation of $11,000. Under the assumption that house prices are normally distributed, find a 90% confidence interval for the mean sales price of all houses in this community. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to the nearest whole number (If necessary, consult a list...
Suppose that a random sample of ten recently sold houses in a certain city has a mean sales price of $295,000, with a standard deviation of $14,000. Under the assumption that house prices are normally_distributed, find a 99% confidence interval for the mean sales price of all houses in this community. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to the nearest whole number. (If necessary, consult a list of...
A certain brokerage house wants to estimate the mean daily return on a certain stock. A random sample of 13 days yields the following return percentages: -287-2.57.-2.52,28.-11.028, 261,-0.96, 2.45,229.1.47, 148,-0.26 If we assume that the returns are normally distributed, find a 95% confidence interval for the mean daily return on this stock. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (if necessary, consult a list of...
Suppose that a random sample of 20 adults has a mean score of 74 on a standardized personality test, with a standard deviation of 7. (A higher score indicates a more personable participant.) If we assume that scores on this test are normally distributed, find a 90% confidence interval for the mean score of all takers of this test. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal...
A random sample of 15 subjects was asked to perform a given task. The time in seconds it took each of them to complete the task is recorded below: 44, 40, 28, 44, 28, 41, 37, 31, 43, 48, 29, 44, 45, 32, 31 Send data to Excel If we assume that the completion times are normally distributed, find a 95% confidence interval for the true mean completion time for this task. Then complete the table below. Carry your intermediate...
A random sample of 15 health maintenance organizations (HMOs) was selected. For each HMO, the co-payment (in dollars) for a doctor's office visit was recorded. The results are as follows: 9, 12, 8, 12, 7, 5, 5, 6, 6, 11, 12, 11, 10, 8, 10 Send data to Excel Under the assumption that co-payment amounts are normally distributed, find a 90% confidence interval for the mean co-payment amount in dollars. Then complete the table below. Carry your intermediate computations to...
The union for a particular industry has determined that the standard deviation of the daily wages of its workers is $21. A random sample of 50 workers in this industry has a mean daily wage of $118. Find a 90% confidence interval for the true mean daily wage of all union workers in the industry. Then complete the table below Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. What is the...
Consider the following random sample of diameter measurements (in inches) of 19 softballs: 4.83, 4.77, 4.85, 4.88, 4.81, 4.7, 4.81, 4.9, 4.75, 4.73, 4.71, 4.76, 4.84, 4.83, 4.69, 4.68, 4.68, 4.7, 4.81 Send data to Excel If we assume that the diameter measurements are normally distributed, find a 90% confidence interval for the mean diameter of a softball. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to two decimal places....
The standard deviation of test scores on a certain achievement test is 11.1. A random sample of 60 scores on this test had a mean of 75.4. Based on this sample, find a 95% confidence interval for the true mean of all scores. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. What is the lower limit of the 95% confidence interval? What is the upper limit...
A random sample of 14 subjects was asked to perform a given task. The time in seconds it took each of them to complete the task is recorded below: 32, 48, 32, 28, 31, 45, 40, 36, 41, 49, 45, 42, 39, 27 Send data to Excel If we assume that the completion times are normally distributed, find a 90% confidence interval for the true mean completion time for this task. Then complete the table below. Carry your intermediate computations...