Given a sample mean difference of 23, a standard error of 4.2, and a critical t value of 2.262, what are the values for the confidence interval?

(13.4996, 32.5004)

Step-by-step explanation:

The confidence interval for mean difference is given by :-

,

where = sample mean difference .

= critical t value (two-tailed)

SE= Standard error.

Given :

SE= 4.2

Now, the confidence interval for mean difference will be :-

Hence, the required confidence interval : (13.4996, 32.5004)

a. is correct