Question 1058592
The SEM is sigma/sqrt(n)=26/sqrt(230)=1.714
That means that although the mean of the sampling distribution is the same, the SD is much less. It is very unlikely all of the 230 observations will be 1 SD to one side or the other of the mean.
The 99% CI uses z=2.576
z*SEM is the interval width is 4.415
(21.585,30.415)