confidence intervals for a population mean

A sample of the reading scores of 35 sixth graders has a mean of 82. If the 95% confidence interval for the population mean of the reading scores of all fifth graders is between 77 and 87, then which among the following choices represents the 99% ..

A sample of scores of 250 candidates has a mean of 47.2 with a standard deviation of 18.6. Find 90% and 95% confidence interval of the population mean and determine which is larger? => (45.3, 49.1) and (44.9, 49.5) and 95% or (45.26, 49.14) and (44...

95% confidence interval of a population mean worked out on a sample size of 10 is, 0.26 < μ < 0.38. What is the likely 95% confidence interval of the mean of the same population worked out on a sample size of 2..

The manager of a company wishes to estimate the average age of the present employees. From the past records, the standard deviation is found to be 8 years. A sample of 100 employees are selected and the mean is found to be 42.8 years. Find the 99% confidence interval o..

95% confidence interval of a population mean with a sample size of 18 was found out as 6.17 < μ < 6.99. Another study calculated the 95% confidence interval as 5.71 < μ < 7.46. Which among the following can be the possibl..

An education department conducted a survey of 400 students on their family background. The results revealed that the mean age of adolescent students who belong to high income families was 15.2 years. The standard deviation of the population is observed as 0.6 years. Find the 99%..

A survey of 139 athletes found that the mean body weight of an athlete is 261.35 pounds. The standard deviation is 2.37, find the 90% confidence interval of the population mean (μ). => 260 < μ < 262 or 261 < μ < 261.70 or 261.02..

A management firm wants to estimate the mean cost of repairing the apartments that are vacated by tenants. A sample of 18 vacated apartments resulted in a mean repair cost of $109 with a standard deviation of $12. Find the 90% confidence interval to estimate ..

A random sample of 52 days taken at a chemical laboratory shows that an average of 36 specimens were tested per day. The standard deviation of the population is 6. I. Find the 99% confidence interval of the mean number of specimens tested each day at the labo..

The rainfall readings (in millimeters) of 9 cities are listed here. Based on the sample, what is the point estimate of the mean? Find the 90% confidence interval of the population. 2.0, 2.8, 3.1, 4.4, 3.9, 2.6, 5.4, 4.7, 5.2 => 3.79 and 2.87 < μ < 4...