A principal randomly slected 6 students to take an aptitude test, their scores were 83, 84.1, 83.5, 83.7, 84.1, and 73.5. construct a 90% confidence interval for the mean score for all students. Assume the population has a normal distribution.
A principal randomly slected 6 students to take an aptitude test, their scores were 83, 84.1, 83.5, 83.7, 84.1, and 73.5. construct a 90% confidence interval for the mean score for all students. Assume the population has a normal distribution.
Compute the sample mean and the unbiased estimate from the sample of the population SD .
Then the interval you require is: where is the point for the cumulative t-distribution with degrees of freedom.