A train travels at a certain average speed for a distance of 54 km and then travels a distance of 63 km at an average speed of 6 km/h more than the first speed. If it takes 3 hours to complete the total journey, what is its first speed?
Let x be the first speed of the train.
We know that `t=3 hours` Thus,we have,
`(x+3)=0 or (x-36)=0`
`x=-3 " or " x=36`
Speed cannot be negative and hence intial speed of the train is 36 km/hour.