As I am guessing you know.. Displacement is the actual amount traveled from the starting point. Saying that 735 m of distance was walked means nothing in this problem. Your questions is very confusing, but basically if you go south 10 meters than north 10 meters that would be 20 meters of distance, but 0 meters of displacement. Or if you went 10 meters west and then 10 meters east that would also be 20 meters distance and 0 meters displacement. If you are going south and then south again the displacement would add since you are actually ending at a point farther away from where you started.