Q. 114.6( 7 Votes )

# An express train takes 1 hour less than a passenger train to travel 132 km between Mysore and Bangalore (without taking into consideration the time they stop at intermediate stations). If the average speed of the express trains is 11 km / hr more than that of the passenger train, find the average speeds of the two trains.

Answer :

Time = distance/speed

Now, express train takes 1 hour less than a passenger train to travel 132 km between Mysore and Bangalore. The average speed of the express trains is 11 km / hr more than that of the passenger train.

Let the average speed of passenger train be ‘a’.

⇒ 132 ×(a + 11 –a) = a^{2} + 11a

⇒ a^{2} + 11a – 1452 = 0

⇒ a^{2} + 44a – 33a – 1452 = 0

⇒ a(a + 44) – 33(a + 44) = 0

⇒ (a + 44)(a – 33) = 0

⇒ a = 33 km/hr

Speed of express train = 44 km/hr

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