10.16 [EX10-016] All students who enroll in a certain memory course are given a pretest before the course begins. At the completion of the course, 10 students are selected at random and given a posttest; their scores are listed here.

Student 1 2 3 4 5 6 7 8 9 10 Before 93 86 72 54 92 65 80 81 62 73 After 98 92 80 62 91 78 89 78 71 80 MINITAB was used to find the 95% confidence interval for the mean improvement in memory resulting from taking the memory course, as measured by the difference in test scores (d  after  before). Verify the results shown on the output by calculating the values yourself. Assume normality.

Confidence Intervals Variable N Mean StDev SE Mean 95% C.I.

C3 10 6.10 4.79 1.52 (2.67, 9.53)