One train is 250 m longer than the other train . When they move in opposite direction they cross each other in 19 seconds and when they move in same direction they take \(\frac{5}{3}\) times time. If speed of faster train is 36 km/hr then find the speed of slower train .
Answer & explanation
Correct answer: option 2
Distance = Speed × Time
Ratio of time taken by trains when they move in same direction to the time taken when they move in opposite direct
Ratio Opposite direction : Same direction
19 : 19 × \(\frac{3}{5}\)
5 : 3
Let speed of faster train = F km/hr
and speed of slower train = S km/hr
Relative speed when trains move in opposite direction = ( F + S ) = 5R
Relative speed when trains move in same direction = ( F - S ) = 3R
F = \(\frac{5R \; + \;3R}{2}\) = 4R
S = \(\frac{5R \; - \;3R}{2}\) = 1R
Ratio of speed of faster train to slower train ,
Ratio F : S
4 : 1
According to question , 4R = 36 km/hr ⇒ 1R = 9 km/hr
speed of slower tain = 9 km/hr