I need help with the following questions and appreciate any and all help given.

Question

1. Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by a 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. The firm examined 35 randomly chosed fax transmissions during the next year, yielding a sample mean of 14.44 with a standard deviation of 4.45 pages. (a)at the .01 level of significance, is the true mean greater than 10? (b) use excel to find the right-tail p-value.

Answer 1

Ho: µ ≤ 10 -->null hypothesis
Ha: µ > 10 -->alternative hypothesis

Using the z-test formula to find the test statistic:
z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size)
z = (14.44 - 10)/(4.45/sqrt of 35)

I'll let you finish the calculation.

If the test statistic exceeds the critical value from the z-table at .01 level of significance for a one-tailed test (the alternative hypothesis shows a specific direction), the null will be rejected in favor of the alternative hypothesis and µ > 10.

The p-value is the actual level of the test statistic.

I hope this will get you started.

Answer 2

Thanks for all of your help.

Answer 3

Thanks for explaining the problem in terms that I can understand.