Question

A train travels 360 km at a uniform speed if the speed had been 5 km more it would have taken 1 hour less for the same johnny find the speed of the train

Answer 1

Speed of the train is 40 km/hr ...

Answer 2

Let the speed of the train be x KMPH

Distance travelled by the train =360KM

Time taken= 360 (x +5)-360 (x) /x (x +5) = 1

                  = 360x + 1800 - 360x / x² + 5x = 1

                  = x²  - 5x = 1800

                  = x²  - 5x -1800 = 0

                  = x² + 45x - 40x - 1800 = 0     (Split the middle term)

                  = x (x + 45) - 40(x + 45) = 0  

                  = (x + 45) (x - 40) = 0

x + 45 = 0   (or) x - 40 = 0

x = -45        (or) x = 40

x cannot be negetive.

∴ x = 40