Expert answer:https://newclassroom3.phoenix.edu/Classroom/#/contextid/OSIRIS:51610247/context/co/view/activityDetails/activity/61dcb793-c0a7-4d62-9dbf-7987016f3214/expanded/FalseReview the Payment Time Case Study and Data Set. Develop a 700-word report including the following calculations and using the information to determine whether the new billing system has reduced the mean bill payment time:Assuming the standard deviation of the payment times for all payments is 4.2 days, construct a 95% confidence interval estimate to determine whether the new billing system was effective. State the interpretation of 95% confidence interval and state whether or not the billing system was effective.Using the 95% confidence interval, can we be 95% confident that µ ≤ 19.5 days?Using the 99% confidence interval, can we be 99% confident that µ ≤ 19.5 days?If the population mean payment time is 19.5 days, what is the probability of observing a sample mean payment time of 65 invoices less than or equal to 18.1077 days? Format your assignment consistent with APA format. Click the Assignment Files tab to submit your assignment.
