Two trains are running on parallel tracks in the same direction at the speed of 80 km/h and 90 km/h, respectively. The trains crossed each other in 3 minutes. If the length of one train is 230 m, then what is the length (in m) of the other train?
Answer & explanation
Correct answer: option 1
According to question ,
The relative speed of the trains = 90 - 80 = 10 km/h
x km/h = x × \(\frac{5}{18}\) m/sec = y m/sec
Speed in m/sec = 10 × \(\frac{5}{18}\)
= \(\frac{25}{9}\) m/sec
Let the length of the other train be x m
Now,
\(\frac{(230+x)× 25}{9}\) = 180
(230 + x) = 180 × \(\frac{25}{9}\)
230 + x = 500
x = 270
So, length of the other train = 270 m