Answer:
The speed of the train is 40 km/h.
Step-by-step explanation:
Since a train travels a distance of 120 km at a constant speed of V km / h, and if the speed is reduced by 10km / h, then the time taken to the journey is increased by one hour, to find the constant speed V of the train, the following calculations must be performed:
20 x 6 = 120
10 x 7 = 140
30 x 4 = 120
20 x 5 = 100
40 x 3 = 120
30 x 4 = 120
Therefore, the speed of the train is 40 km/h.
