Answer Happy

10.61 According to a Bureau of Labor Statistics report released on May 15, 2018, financial analysts earn an average of $100,990 a year and engineers earn an average of $99,230 a year (www.bls.gov). Suppose that these estimates are based on random samples of 1600 financial analysts and 1400 engineers. Further assume that the sample stan- dard deviations of the annual earnings of these two groups are $12,200 and $11,500, respectively, and the population standard deviations are unknown and unequal for the two groups. a. Construct a 98% confidence interval for the difference in the mean annual earnings of the two groups, financial analysts and engineers. b. Using a 1% significance level, can you conclude that the aver- age annual earnings of financial analysts is higher than that of engineers?