Concept:When two runners reach the same time, their time taken must be equal.Explanation:Let the speed of Q be x m/s.Since P runs 232​=38​ times as fast as Q,Speed of P =38​x.Let the winning post be at distance d m from P’s starting point.Q gets a start of 80 m, so Q runs only d−80 m.Time taken by P:tP​=38​xd​=8x3d​Time taken by Q:tQ​=xd−80​Since they reach the winning post at the same time:8x3d​=xd−80​Cancel x from both sides:83d​=d−80Multiply by 8:3d=8d−6405d=640d=128 mAnswer:128 mCorrect option: D. 128 m