Question

A train travels 300km at a constant speed.If the speed of the train is increased by 5 km/hour the journey would have taken 2hrs less.

Answer 1

Let x km/hr be the constant speed of the train,
Then Time taken to cover 300km = 300/x hrs

Time taken to cover 300km when the speed is increased by 5km/hr= 300/x+5 hours

It is given that the time to cover 300km is reduced by 2 hours

But x cannot be negative. Therefore x=25

Hence, the original speed of the train is 25km/hr