Posted by Mara Cross on November 10, 2002 at 22:01:17:
A sample of 22 public high school students spent an average of 6.5 hours studying per week.
Assuming the distribution of hours spent studying is near normal and the standard deviation is 2.3 hour, find a 95% confidence interval for the mean number of hours spent studying by public high school students. Give your interpretation of the interval.
I know the answer is 5.54 to 7.46. what I want to know is how to get it.
So far I have the margin of error for a 95% confidence interval is 1.96
and so I have 22+1.96 =sigma over the square root of /n. Which is 2.3 over 22. Doing that I come up with. 1.4 then n=(1.43)sq=20.49
So now I don't know if this is even right?
Post a Followup