The Payment Time Case QNT 561

The Payment Time Case Statistical analysis is used in many ways when it comes to finding out how accurate a new systems design and effectiveness to a company is. The information can cause a business many dollars and could be its livelihood in the long-run. In this situation, a consulting firm, has recently developed an electronic billing system for Stockton Trucking Company that will send invoices to the customer that will also check and correct errors. This system is believed to reduce the amount of time that it takes for customers to make payments. Assuming the standard deviation of the payment times for all payments is 4.2 days, construct a 95% confidence interval I will estimate and determine whether the new billing system was...