If one train m long, the length of other train is :

Two trains running in opposite directions at 36 kmph and 45 kmph cross each other in 20 seconds. If one train 200 m long, the length of other train is

  1. 200 m.
  2. 144 m.
  3. 250 m.
  4. 240 m.
Anurag Mishra Professor Asked on 14th December 2015 in Maths.
Add Comment
  • 2 Answer(s)


    Solution: Question is incomplete if we take first train length 200 m then the respective speed of both trains in opposite side will be (36+45)=81 Km/h

    Speed =81 x 5/18
    =45/2 m/sec 
    If both trains cross each other in 20 secs then total length of both trains (Distance)= Speed X Time 
      =45/2X20 =450 m then the length of another train=450-200=250 m
    So option (3) will be correct.

    HALCYONJK Newbie Answered on 16th December 2015.
    Add Comment

    Answer: (3) 250 m

    Explanation:-
    Let the length of another train be X m.
    The respective speed of both trains in opposite side = 36 + 45
    = 81 km/hr
    Speed in m/sec = 81 x 5/18
    = 9 x 5/2
    = 45/2 m/sec

    If both trains cross each other in 20 sec
    Then, total length of both trains = 45 x 20/2 = (X + 200)
    900/2 = X + 200
    X = 450 – 200
    X = 250 m

    Then, the length of another train is 250 m.

    Hence, correct answer is option (3) 250 m.

    Anurag Mishra Professor Answered on 16th December 2015.
    Add Comment
  • Your Answer

    By posting your answer, you agree to the privacy policy and terms of service.