The TIV Telephone Company provides long-distance telephoneservice in an area. According to the company’s records, the averagelength of all long-distance phone calls placed through this companyin 2015 was 12.44 minutes. The company’s management wants to checkif the mean length of the current long- distance calls is differentfrom 12.44 minutes. A sample of 150 such calls placed through thecompany produced a mean length of 13.71 minutes. The standarddeviation of all such calls is 2.65 minutes. Using a 2% level ofsignificance, can you conclude that the mean length of all currentlong-distance calls is different from 12.44 minutes? Hypothesis tobe tested (in words): Hypothesis to be tested (using symbols): H0 :H1 : Is this problem a (circle one): left-tailed test, right tailedtest, or a two-tailed test? a= ,x= ,sors= ,n= .
Test statistic =
The p-value =
Reject or fail to reject H0 (circle one) Rejection region(picture): Conclusion (in words):
