The speed of a passenger train is x km/h. An express train is 20 km/hr faster than the passenger train and takes 1 hr 40 minutes less than the passenger train to cover a distance of 200 km. Calculate their speed.
Copyright © 2024 EHUB.TIPS team's - All rights reserved.
Answers & Comments
Answer:
Let x be the speed of express train
speed of slower train = x-12
travel time = distance / speed
[240/(x-12)] -[240/x] =1
Least Common Divisor of the above fractions is
x(x-12)
240x - 240x + 2880=x2 - 12x
x2 -12x - 2880 = 0
(x+48)(x-60)=0
x = - 48 or x = 60
As speed cannot be negative, we discard the result x= -48.
Therefore, speed of the express train is 60 km/hr
Step-by-step explanation: