Rita was running on a 500 metre track at a rate of 100 metres per minute. One minute after Rita started, Liz started running from the same starting point on the track at 150 metres per minute. What is the shortest time that Liz could run on the track in order to meet up with Rita?
Select:  A) 4 minutes  B) 3 minutes  C) 2 minutes  D) 1.6 minutes  E) 1 minute
we don't need to assume here the direction.we need to find which will take less time   so there are 2 cases   1)both moving in same direction...then time would be 2 minutes   2)both moving in opposite direction then time would be 1.6 minutes   as we need the shortest time it would be the second case   Answer:1.6 minutes
<result>D</result>
Rita was running on a 500 metre track at a rate of 100 metres per minute. One minute after Rita started, Liz started running from the same starting point on the track at 150 metres per minute. What is the shortest time that Liz could run on the track in order to meet up with Rita?