Question

A train travel 180km distance uniform speed.if the speed of train 9km more it would takes 1hourless for same journey. find its speed of train.​

Answer 1

Step-by-step explanation:

1. At original of train is =x km/h

Distance = 180km

Time =180 / x. hour

speed = (x+9) km/h

distance = 180 km/h

Answer 2

Step-by-step explanation:

Let the speed of train be x km /h

Distance = 180 km

So, time = 180 / x

When speed is 9 km/h more, time taken = 180 / x+9

According to the given information:

180 / x - 180 / x+9 = 1

180 (x+9-x) / x(x+9) = 1

180 * 9 = x(x+9)

1620 = x2 + 9x

x2 + 9x - 1620 = 0

x2 + 45x - 36x - 1620 = 0

x(x+45) - 36(x+45) = 0

(x-36)(x+45) = 0

x = 36 or -45

But x being speed cannot be negative.

So, x = 36

Hence, the speed of the train is 36km/h.