Answer:
24.6 < μ < 27.2
Step-by-step explanation:
We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of .
So it is z with a pvalue of , so
Now, find the margin of error M as such
In which is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 25.9 - 1.3 = 24.6 pounds.
The upper end of the interval is the sample mean added to M. So it is 25.9 + 1.3 = 27.2 pounds.
So the correct answer is:
24.6 < μ < 27.2