A fast train takes one hour less than a slow train for a journey of 200 km. If the speed of the slow train is 10 km / hr less than that of the fast rain, find the speed of the two trains.

Question

Philoid · Accepted Answer

Speed = distance/time

Let the speed of the faster train be ‘a’ km/hr.

Speed of the slow train = a – 10 km/hr

Also, fast train takes one hour less than a slow train for a journey of 200 km.

⇒ 200a + 2000 – 200a = a² – 10a

⇒ a² – 10a – 2000 = 0

⇒ a² – 50a + 40a – 2000 = 0

⇒ a(a – 50) + 40(a – 50) = 0

⇒ (a + 40)(a – 50) = 0

⇒ a = 50 km/hr

Speed of the trains is 50 km/hr, 40 km/hr