Without stoppages, the speed of a train is 150 km/h and

Without stoppages, the speed of a train is 150 km/h and with stoppages, it is 100 km/h. How many minutes does the train stop ?

Because of stoppages, train covers 50 km less per hour.
∴ Time taken taken to cover 50 km = 50/150 h = (50/150) x 60 = 20 min