Question
In: Statistics and Probability
A librarian claims that the mean number of books read per month by community college students...
- A librarian claims that the mean number of books read per month by community college students is less than 2 books. A random sample of 28 community college student had read a mean of 2 books with a standard deviation of 2.14 books. Test the librarian’s claim at the 0.01 level of significance.
- State the hypotheses and identify the claim.
- Find the critical value(s)
- Compute the test value.
- Make the decision to reject or not reject the null hypothesis.
- Summarize the results.
Solutions
Expert Solution
Since , the population standard deviation is not known and the sample size is less than 30.
Therefore , use t-test.
A. Hypothesis: 
Vs 
( Claim )
Teh test is one tailed test.
B.df=degrees of freedom=n-1=28-1=27
The critical value is ,
; From t-table
C. The test statistic is ,
D. Decision : Here , the value of the statistic does not lies in the rejection region.
Therefore , fail to reject Ho.
E. Conclusion : Hence , there is not sufficient evidence to support the claim that the mean number of books read per month by community college students is less than 2 books.
orchestra answered 2 years agoRelated Solutions
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