Difference Between the Two Population Mean Scores Questions

From a random sample of 7 students in an introductory finance class that uses group-learning techniques, the mean examination score was found to be 76.07 and the sample standard deviation was 2.3.

For an independent random sample of 8 students in another introductory finance class that does not use group-learning techniques, the sample mean and standard deviation of exam scores were 73.81 and 8.6, respectively. Estimate with 90%

confidence the difference between the two population mean scores; do not assume equal population variances.

The 90% confidence interval is from a lower limit of to an upper limit of .

(Round to two decimal places as needed.)