confidence intervals

Based on a sample of 150 U.S couples, it was found that in 108 couples the children are taller than the couples. Find the 95% confidence interval for the proportion of all U.S couples where children are taller than the parents. => 68.3% < p < 75.7% or 64.8% < p < 79...

95% confidence interval of a population mean(μ) with a sample size of 60 was found out as 14.5 < μ < 17.6. Another study calculated the 95% confidence interval as 14.3 < μ < 17.8. Which among the following can be the possible sample size ..

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 laboratory. II. Find the..

Select the correct statement(s). I. An interval estimate always contains the value of the parameter being estimated. II. To be more confident that the interval contains the true population mean, the interval shall be more narrow. => I only or II only or none ..

A standard notebook is supposed to have on an average, 200 pages, with a standard deviation of 2 pages. From a supply of 2500 notebooks, a random sample of 40 notebooks was taken and found that the mean number of pages in the notebook was 197. Determine the 95% confidence interval..

For a sample mean of 35.3, and a given standard deviation the 95% confidence interval for a population mean was calculated as 33.894 < μ < 36.316. Which is the correct representation after rounding the values? => 33.894 < μ < 36.316 or 33.89 < μ < 36.3..

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 < μ < 261.68 or 260...

For 99% confidence interval, when t ∝ /2 is 2.878, which of the following could be the sample size? => 19 or 9 or 100 or 18..

What are the 95% and 99% confidence intervals for the population mean, if the variance is 0.64? Given that sample size = 60, sample mean = 11.21. => (11.29, 11.371) and (10.933, 11.467) or (10.997, 11.403) and (10.997, 11.403) or (11.01, 11.41) and (10.94, 11.48) or (11.29, 11.3..

A magazine report stated that the average business traveler will spend $180 per week on calls. A sample of 20 business travelers are selected at random and their mean expenses was found as $185 with a standard deviation $15. Is there enough evidence to reject the report at α = 0.01. Also, fin..