posted by Anna .
Runner A is initially 5.0 km west of a flagpole and is running with a constant velocity of 4.5 km/h due east. Runner B is initially 7.0 km east of the flagpole and is running with a constant velocity of 6.5 km/h due west. How far are the runners from the flagpole when their paths cross?
The distance between them is initially 12 km and decreases at a rate 4.5 + 6.5 = 11 km/h.
They meet after = = 12/11 = 1.091 hours. A will have run 4.909 km east and B will have run 7.091 km east at that time.
They will both be 4.909 - 4.5 = 0.409 km east of the flagpole at that time.