You are given the sample mean and the population standard deviation. Use this information to construct the 90% and 95% confidence intervals for the population mean Interpret the results and compare the widths of the confidence intervals.
From a random sample of 78 dates, the mean record high daily temperature in a certain city has a mean of 86.68°F Assume the population standard deviation is
13 58°F
The 90% confidence interval is (.
(Round to two decimal places as needed)
The 95% confidence interval is D.
(Round to two decimal places as needed)
Which interval is wider? Choose the correct answer below
The 90% confidence interval
The 95% confidence interval
Interpret the results
CA. You can be 90% confident that the population mean record high temperature is between the bounds of the 90% confidence interval, and 95% confident for
the 95% interval
• B. You can be certain that the mean record high temperature was within the 90% confidence interval for approximately 70 of the 78 days, and was within the
95% confidence interval for approximately 74 of the 78 days
C. You can be 90% confident that the population mean record high temperature is outside the bounds of the 90% confidence interval, and 95% confident for the
D. You can be certain that the population mean record high temperature is either between the lower bounds of the 90% and 95% confidence intervals or the
upper bounds of the 90% and 95% confidence intervals
m
95 interval