Use the given degree of confidence and sample data to construct a confidence interval for the population mean, µ. Assume that the population has a normal distribution.
A sociologist develops a test to measure attitudes towards public transportation, and 27 randomly selected subjects are given the test. Their mean score is 76.2 and their standard deviation is 21.4. Construct the 95% confidence interval for the mean score of all such subjects.
Answer
64.2 < µ < 88.2
67.7 < µ < 84.7
69.2 < µ < 83.2
74.6 < µ < 77.8