Question

a yrain travels 180 km at uniform speed. if the speed had been 9km mire, it would have taken 1hour less for the same journey. find the speed of the train​

Answer 1

Answer:

Let the speed of the train be xkmph

The time taken by the train to travel 180km is

x

180

h

The increased speed is x+9

The time taken is

x+9

180

According to the question,

The time taken is

x

180

−1

⟹

x

180

−1=

x+9

180

⟹

x

180−x

=

x+9

180

⟹180x−x

2

+1680−9x=180x

⟹x

2

+9x−1680=0

⟹x

2

+45x−36x−1680=0

⟹x(x+45)−36(x+45)=0

x=36,−45