For Exercises 29–49, assume normality and use Welch's test and interval unless otherwise indicated.
35. Engineering Starting Salaries. The National Association of Colleges (NAC) reports mean starting salaries for college graduates in various disciplines. NAC reported that the mean salary for 2014 engineering graduates was $62,719, whereas the mean salary for 2013 engineering graduates was $62,535. Assume that these statistics were drawn from independent samples of size 100, each with a sample standard deviation of $10,000. Test whether there was a significant change in the salary of engineering graduates from 2013 to 2014, using level of significance .
10.2.35
versus ; Reject if the . . (TI-84: 0.8966133443). The is not , so we do not reject . There is insufficient evidence at level of significance that the population mean salary of engineering graduates has changed from 2013 to 2014.