Based on these sample statistics, compute the 95% confidence interval for the average delivery time. a.[15.366, 25.754]b.[20.159, 25.754]c.[20.195, 20.169]d.[ 20.159, 20.961]

The R# Medical Centre undertook a survey to determine the average waiting time of patients in the surgery before they saw a doctor. From 14 responses, the average and standard deviation of the waiting times was found to be 26.6 and 16.37 minutes, respectively. Assuming the information was collected through a random sample and that the waiting time is approximately normally distributed, calculate a 95% confidence interval for the mean waiting time at the medical centre. State the lower bound (in minutes) correct to 3 decimal places.

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.37, 33, 28, 29, 37, 50, 28, 45, 49, 30, 39, 27, 40, 48, 26Send data to calculatorIf we assume that the completion times are normally distributed, find a 95% confidence interval for the true mean completion time for this task. Give the lower limit and upper limit of the 95% confidence interval.Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place. (If necessary, consult a list of formulas.)Lower limit: Upper limit:

Based on your results, which of the following is TRUE? Use the significance level of 0.05 for your analysis.a.There is enough evidence to suggest that the average delivery time is longer than 20 minutes.b.There is enough evidence to suggest that the average delivery time is less than 20 minutes.c.There is not enough evidence to suggest that the average delivery time is longer than 20 minutes.d.There is not enough evidence to suggest that the average delivery time is less than 20 minutes.

Internet connections are often slowed by delays at nodes. Let us determine if the delay time increases during heavy-volume times. Four hundred packets are sent through the same network between 5 pm and 6 pm (sample X ), and four hundred packets are sent between 10 pm and 11 pm (sample Y ). The early sample has a mean delay time of 0.7 sec with a standard deviation of 0.11 sec whereas the second sample has a mean delay time of 0.6 sec with a standard deviation of 0.09 sec.Construct a 99.5% confidence interval for the difference between the mean delay times.

Construct a 95% confidence interval for the population mean based on a sample of measurements2.6, 8.4, 3.0, 5.5, 6.4, 8.1if measurement errors have Normal distribution, and the measurement device guarantees a standard deviation of σ  = 2.3.