u50 Example 8.5 Auditors (Confidence interval) An accounting firm conducts a random sample of the accounts payable for the cast and the west offices of one of its clients. From these two independent samples the company wants to estimate the difference between the population mean values of the payables The sample statistics obtained are as follow KANTOR West (HOIATON X PRIATINY Sample man 5290 Samples 16 11 Sample standard deviation SO We do not mume that the unknown population variances are equal. Estimate the dif- fermee between the mean values of the payables for the two offices. Use 95% conti dience level