Find the 99% confidence interval.

Question

 You must estimate the mean temperature (in degrees Fahrenheit) with the following sample temperatures. Assume the temperatures are normally distributed. Find the 99% confidence interval.

Temperature

77

78

75

76

73

77

Answer 1

Compute the mean and standard deviation

Determine t-critical for sample size of 6 (5 degrees of freedom) and tail alpha of 0.005.

The confidence interval =

mean +/- t-critical * standard deviation/square root(sample size)