The Following Are the Achievement Test Results for 15 Matched $(\mu_A - \mu_B)$

Short Answer

The following are the achievement test results for 15 matched pairs taught by Method A and Method B.
(a)Construct the 95% confidence interval for $(\mu_A - \mu_B)$ .
(b)Ignore thecorrelation coefficient and treat the two samples as though they were independent. Construct the 95% confidence interval for $(\mu_A - \mu_B)$ .
(c)What does a comparison of the answers to (a) and (b) suggest concerning the effect on interval estimates of using samples?