Q10 of 58 Page 118

An express train takes 1 hour less than a passenger train to travel 132 km between Mysore and Bengaluru (with out taking into consideration the time they stop at intermediate stations). If the average speed of the express train is 11 km/h more than that of the passenger train find the average speed of the two trains.

Let speed of passenger train be x and express train be x + 11

Distance travelled = 132 km


Time difference between the two trains = 1 hours



⇒ 132x + 1452 - 132x = x(x + 11)


⇒ x2 + 11x - 1452 = 0


Performing factorization we get:


⇒ x2 + 44x - 33x - 1452 = 0


⇒ x(x + 44) - 33(x + 44) = 0


⇒ (x - 33)(x + 44) = 0


⇒ x = 33, - 44


Since speed cannot be negative so


Speed of Passenger train = 33 kmph


Speed of Express Train = (33 + 11) = 44 kmph


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