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At your part-time job in the office, your manager requested that you examine all accounts receivable of the company, and then to take a random sample of them to provide her with estimates of the population values useful for decision making. You considered a random sample of 48 of the accounts and obtained a mean of $138.55 and a standard deviation of $50.28. Assuming normality for the distribution of amounts in the accounts receivable, estimate the upper end point in a 90% confidence interval for the total amount of the 805 accounts of the company.

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The partial results below are based on a sample of recently trained workers, to determine if the number of hours of training time received (X, in hours) has helped in improving the time taken to troubleshoot a process problem (Y, in minutes).

Summary Statistics Variable N Mean Variance Corrected SS (SSxx) X 26 7.04 5.238462 130.9615 Y 26 16. 1538462 19.33538 483.3846 Parameter Estimates Variable Parameter Standard Estimate Error Intercept 29.32952 0. 65182 Training (X) -1.87195 0. 08823 Standard Error 1.00971 R-Square 0.9494