4- (14%) A random sample of 10 yields a mean and standard deviation, respectively, of 80...
4- (14%) A random sample of 10 yields a mean and standard deviation, respectively, of 80 and 7.9. Does this sample confirm that the population mean is greater than 78 with 95% confidence level?
4- (14%) A random sample of 10 yields a mean and standard deviation, respectively, of 80 and 7.9. Does this sample confirm that the population mean is greater than 78 with 95% confidence level?
4- (14%) A random sample of 10 yields a mean and standard deviation, respectively, of 80 and 7.9. Does this sample confirm that the population mean is greater than 78 with 95% confidence level?
4- (14%) A random sample of 10 yields a mean and standard deviation, respectively, of 80 and 7.9. Does this sample confirm that the population mean is greater than 78 with 95% confidence level?
4- (14%) A random sample of 10 yields a mean and standard deviation, respectively, of 80 and 7.9. Does this sample confirm that the population mean is greater than 78 with 95% confidence level?
A random sample of 250 persons yields a sample mean of 110 and a sample standard deviation of 10. Construct three different confidence intervals to estimate the population mean, using 95%, 99%, and 99.9% levels of confidence. What happens to the interval width as the confidence level increases? Why?
A normally distributed population has a mean of 500 and a standard deviation of 80. a. Determine the probability that a random sample of size 25 selected from this population will have a sample mean less than 463 . b. Determine the probability that a random sample of size 16 selected from the population will have a sample mean greater than or equal to 538. A company makes windows for use in homes and commercial buildings. The standards for glass...
A simple random sample with n = 50 provided a sample mean of 23.5 and a sample standard deviation of 4.2. a. Develop a 90% confidence interval for the population mean (to 1 decimal). b. Develop a 95% confidence interval for the population mean (to 1 decimal). c. Develop a 99% confidence interval for the population mean (to 1 decimal). d. What happens to the margin of error and the confidence interval as the confidence level is increased?
The yields from an ethanol-water distillation column have a standard deviation of 1%. A random sample of eight recent bathes produced these yields 0.90 0.93 0.95 0.86 0.90 0.87 0.93 0.92 For the above 8 observations, the sample mean is 0.9075 and the standard deviation of this sample is s = 0.031. (a) Construct a 95% confidence interval for the true mean yield. (b) We are interested in testing H0: µ = 0.95 versus Ha µ ≠ 0.95. Use your...
A simple random sample of 60 items resulted in a sample mean of 80. The population standard deviation is σ =15 . a. Compute the 95% confidence interval for the population mean. Round your answers to one decimal place. ( , ) b. Assume that the same sample mean was obtained from a sample of 120 items. Provide a 95% confidence interval for the population mean. Round your answers to two decimal places. ( , )