A train 700 m long passes a person walking at 5 km/h in the same direction in 28 seconds. What is the speed of the train?

💡 Solution & Explanation

When both move the same way, the train passes the person at the difference of their speeds. That relative speed = 700 m ÷ 28 s = 25 m/s = 25 × 18/5 = 90 km/h. So the train's own speed = 90 + 5 = 95 km/h. Forgetting to add the walking speed gives 90 km/h.