Afair isaac corporation (fico) score is used by credit agencies to assess the creditworthiness of individuals. values range from 300 to 850, with a fico score over 700 considered to be a quality credit risk. a credit analyst wondered whether high-income individuals had higher credit scores. he obtained a random sample of 40 high-income individuals and found the sample mean credit score to be 714.2 with a standard deviation of 83.2. conduct the appropriate test to determine if high-income individuals have higher fico scores at the = 0.05 level of significance.