Faced with rising fax costs a firm issued a guideline that t

Faced with rising fax costs, a firm issued a guideline that transmissions of 8 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 8 or below. The firm examined 29 randomly chosen fax transmissions during the next year, yielding a sample mean of 9.11 with a standard deviation of 4.42 pages. (a-1) Find the test statistic. (Round your answer to 4 decimal places.) The test statistic (a-2) At the .01 level of significance, is the true mean greater than 8? Yes No (b) Use Excel to find the right-tail p-value. (Round your answer to 4 decimal places.) p-value

Solution

(a-1) t=(xbar-mu)/(s/vn)

=(9.11-8)/(4.42/sqrt(29))

=1.3524

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(a-2) No

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(b) The p-value = P(t with df=n-1=29-1=28 > 1.3524) =0.0935 (from student t table)