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In: Statistics and Probability

A sample of 17 books from James Patterson’s Alex Cross series had an average length of...

A sample of 17 books from James Patterson’s Alex Cross series had an average length of 438.47 pages, with a standard deviation of 26.14. A sample of 18 books from Lee Child’s Jack Reacher series had an average length of 505 pages with a standard deviation of 90.97 pages. Find a 90% confidence interval for the difference between the average length of an Alex Cross novel and that of a Jack Reacher novel and explain what your interval means.

a) The difference between the sample means (x̅1 – x̅2) =

b) The degrees of freedom (df) for this problem =

c) Value of t* =

d) SE for the confidence interval =

e) ME for the confidence interval =

f) Confidence interval =

g) Write your explanation for the confidence interval:

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