A study was conducted in order to estimate μ, the mean number of weekly hours that U.S. adults use computers a

A study was conducted in order to estimate μ, the mean number of weekly hours that U.S. adults use computers at home. Suppose a random sample of 81 U.S. adults gives a mean weekly computer usage time of 8.5 hours and that from prior studies, the population standard deviation is assumed to be σ = 3.6 hours.





Question 2:


Point value: 10








Which of the following will provide a more informative (i.e., narrower) confidence interval than the one in problem 3?








(a) Using a sample of size 400 (instead of 81).





(b) Using a sample of size 36 (instead of 81).





(c) Using a different sample of size 81.





(d) Using a 90% level of confidence (instead of 95%).





(e) Using a 99% level of confidence (instead of 95%).





(f) Both (a) and (d) are correct.





(g) Both (a) and (e) are correct.

A study was conducted in order to estimate μ, the mean number of weekly hours that U.S. adults use computers a
F.





Smaller levels of confidence means smaller margins of error.


And more people surveyed reduces varience.