Answer Happy

if b is t -test what are the degrees of freedom?
Question 17 of 20 (1 point Question Attempt 1 of 1 According to a leasing firm's reports, the mean number of miles driven annually in its leased cars is 13,480 miles with a standard deviation of 1240 miles. The company recently starting using new contracts which require customers to have the cars serviced at their own expense. The company's owner believes the mean number of miles driven annually under the new contracts, less than 13,480 miles. He takes a random sample of 80 cars under the new contracts. The cars in the sample had a mean of 13,280 annual miles driven, is there support for the claim, at the 0.01 level of significance, that the population mean number of miles driven annually by cars under the new contracts, is less than 13,480 miles? Assume that the population standard deviation of miles driven annually was not affected by the change to the contracts. Perform a one-talled test. Then complete the parts below. Carry your intermediate computations to three or more decimal places, and round your responses as specified below. (If necessary, consult a list of formulas.) (6) State the null hypothesis H, and the alternative hypothesis , HO 0 5 H0 8 O OSO WC (6) Determine the type of test statistic to use (Choose one) (c) Find the value of the test statistic (Round to three or more decimal places.) 0 (d) Find the p-value. (Round to three or more decimal places.) D GO DRO (e) Can we support the daim that the population mean number of miles driven annually by cars under the new contracts is less than 13,480 miles? Yes No