Recently, Experian Reported That the Average Credit Score for a New-

Multiple Choice

Recently, Experian reported that the average credit score for a new- car loan was 753. 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 764.2 with a sample standard deviation of 34.5. Ally Financial would like to set α = 0.05. The test statistic for this hypothesis test would be ----- .

A) t x = 2.31
B) t x = 1.45
C) z x = 2.04
D) z x = 1.25