A survey was done with the hope of comparing salaries of chemical plant managers employed in two

Question:

A survey was done with the hope of comparing salaries of chemical plant managers employed in two areas of the country, the northern and west central regions. An independent random sample of 300 plant managers was selected from each of the two regions. These managers were asked their annual salaries. The results are as follows

North West Central T2 = $98, 500 T1 = $102, 300 S1 = $3800 = $5700

(a) Construct a 99% confidence interval for Âµ1 - Âµ2, the difference in the mean salaries.
(b) What assumption did you make in (a) about the distribution of annual salaries for the two regions? Is the assumption of normality necessary? Why or why not?
(c) What assumption did you make about the two variances? Is the assumption of equality of variances reasonable? Explain!

Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...