A psychology teacher gives two identical lessons, one at 8 a.m. and the other

at 1 p.m. A random sample consists of 20 students taking the course

in the morning; they pass the exam with an average of 82 and a standard deviation of 8. The 15 students who take the afternoon course get a

mean of 87 with a standard deviation of 6. Find a confidence interval with

a level equal to 95% for the difference in results between the two groups.

Can we say that the morning group is weaker than the afternoon group using the confidence interval found?