Question

A train travels 360 km at a uniform speed.if the speed had been 5km/h more,it would have taken 1 hour less for the same journey. Find the speed of the train.

Answer 1

Answer:

Step-by-step explanation:

Given,

• A train travels 360 km at a uniform speed.
• If the speed had been 5km/h more, it would have taken 1 hour less for the same journey.

To Find,

• The speed of the train.

Solution,

Let the original speed of the train be x km/h.

Time taken to cover 360 km =  360/x hr

Time taken to cover 360 km at new speed = 360/x + 5 hr

According to the Question,

⇒ 360/x - 360/ x + 5 = 1

⇒ 360 (x + 5 - x)/x(x + 5) = 1

⇒ 360 (5) = x² + 5x ⇒ 1800 = x² + 5x

⇒ x² + 5x - 1800 = 0

⇒ x² + 45x - 40x - 1800 = 0

⇒ x (x + 45) - 40( x + 45) = 0

⇒ (x + 45) (x - 40) = 0

⇒ x = - 45, 40 (Speed cannot be negative)

⇒ x = 40 km/hr.

Hence, the  speed of the train is 40 km/h.

Answer 2

$40 \: km/hr \: is \: the \: speed \: of \: the \: train$