Question 3 A postal letter carrier has a route consisting of

Question 3: A postal letter carrier has a route consisting of five segments with the time in minutes to complete each segment being normally distributed with means and variances as shown: SegmentA N(38,16) SegmentB N99,29) SegmentC N(85,25) Segment D N(73,20) SegmentE N52,12) In addition to the times mentioned, the letter carrier must organize the mail at the central office, which activity requires a time that is distributed by N(90,25). The drive to the starting point of the route requires a time that is distributed by N(10,4). The return from the route requires a time that is distributed by N(15,4). The letter carrier then performs administrative tasks with a time that is distributed by N(30,9) a) b) What is the expected length of the letter carrier\'s work day? Overtime occurs after eight hours of work on a given day. What is the probability that the letter carrier works overtime on any given day?

Solution