Two trains running in opposite directions on parallel tracks, at speeds of 42 km/h and 57 km/h, take 18 seconds to cross each other. If the length of one train is 270 m,then the length of the other train is:
Answer & explanation
Correct answer: option 3
Let the length of the second train be S cm.
According to question ,
Length of the first train = 270 m
Speed of the first train = 42 km/h
Speed of the second train = 57 km/h
Time taken to cross each other = 18 sec
Speed = \(\frac{Distance }{Time}\)
According to the question,
(57 + 42) × \(\frac{5 }{18}\) = \(\frac{(270+S) }{18}\)
99 × 5 = 270 + S
S = 495 – 270
S = 225
So , Length of second train 225 m.