The endpoints of the directed line segment AB are A (4,1) and B (8,7) Find the coordinates of point P along AB so that the ratio of AP to PB is 3 to 1

Monitors manufactured by tsi electronics have life spans that have a normal distribution with a standard deviation of 1800 hours and a mean life span of 20,000 hours. if a monitor is selected at random, find the probability that the life span of the monitor will be more than 17,659 hours. round your answer to four decimal places.