An express train makes a run of 240 km at a certain speed. Another train , whose speed is 12 km/hr less than the first train takes an hour longer to make the same trip . Find the speed of the express train in km/hr.
Let the speed of express train be x km/h Then the speed of ordinary train will be (x-12) km/h.
Time taken by express train =240x
Time taken by ordinary trian=240x−12
According to the given condition:
Since, speed can't be a negative quantity.
So, the speed of the express train is 60 km/h.