Question

According to an Experian report, the average credit score for a new-car loan was 713 at the end of 2017. Suppose Ally Financial, a bank holding company that finances car loans, would like to test the hypothesis that the average credit score has increased since the Experian report. A random sample of 20 new-car loans had an average credit score of 724.2 with a sample standard deviation of 34.5. Ally Financial would like to set a = 0.05. The correct hypothesis statement for this hypothesis test would be OA. HO:2713; Hu<713 OB. Ho: x= 713; H, X*713 0 C. Houý713; H: HỒ713 OD. Ho: u= 713; H: *713

Answer 1

Given, Hypothesized populatim mean = M = 713 Sample size = n = 20 sample meon = x = 724.2 Sample standard deviation as = 345 2=0.05 The null and alternative hypotheses are c. Ho: M4713 : Hi: M7713

Given, Sample size = n = 15 Sample mean = x= 18.2 ounces Sample standard deviation ES=3.9 ounies 2=0.10 The null and altemative hypotheses are Hoi M = 19 vs Ha: > 17 - right-tailed test I Test statistic-fix-M - 18.2-17 3.9 ir IT Test statistic=t=1.1927 critical value = tan- to.10, 15-1 to.10, 14 Turitical value = 1.345/