Please I just need 1,2 I’ll give brainlest ://
1 answer:
You might be interested in
Answer:
(29.13, 30.07)
Step-by-step explanation:
The first step is finding 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 , that is between
and
, so we use
.
Now, find M as such:
In which is the standard deviation and n is the length of the sample
The lower end of the interval is the sample mean subtracted by M. So it is 29.6 - 0.47 = 29.13 hours.
The upper end of the interval is the sample mean added to M. So it is 29.6 + 0.47 = 30.07 hours
The 90% confidence interval is (29.13 hours, 30.07 hours).
The correct answer is:
(29.13, 30.07)