Question 445128: Science fiction novels average 240 pages in length. The average length of 14 randomly chosen novels written by I. M. Wordy was 280 pages in length with a standard deviation of 40. Are Wordy's novels significantly longer than the average? Assume = .05. What is the test value, the critical value(s), and the conclusion?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Science fiction novels average 240 pages in length. The average length of 14 randomly chosen novels written by I. M. Wordy was 280 pages in length with a standard deviation of 40.
--------------------------------
Are Wordy's novels significantly longer than the average?
Assume = .05. What is the test value, the critical value(s), and the conclusion?
======================
Ho: u <= 240
Ha: u > 240 (the question)
----------
Critical Value = invT(0.95 with df = 13) = 1.7709
sample mean = 280
test stat: t(280) = (280-240)/[40/sqrt(14)] = 3.7417..
-------
Since the test stat is in the reject interval, reject Ho.
The test result supports a positive answer to the question.
====================================================================
Cheers,
Stan H.
|
|
|
