Question

a train covers a distance of 90 km at a uniform speed and had the speed been 15 kilometre per hour more it could have taken 30 minutes less for the journey find the original speed of the train ​

Answer 1

30 km per hour will be the uniform speed of the train

Answer 2

We have formula speed = distance / time.

Let the original speed = x

According to questions 90/x and 90/x +15

90/x - 90/x + 15 = 30/ 60

90x + 1350 -90 x / x² +15 x = 1/2

= 2700 = x² + 15x

= x² + 15x - 2700

= x²+60x -45x - 2700

= (x-45)(x +60)

Here, the speed cannot be negative x = 45 km/h