Problem on Trains


  1. The distance between two station A and B is 220 km. A train leaves A toward B at an average speed of 80 km/hr. after half an hour another train leaves B toward A at an average speed at 100 km/hr. the distance of the point of two train meet, from A is ?









  1. View Hint View Answer Discuss in Forum

    Let the required distance be x km.
    Then, ( x/80 ) - ( 220 - x ) / 100 = 1/2

    Correct Option: A

    Let the required distance be x km.

    Then, ( x/80 ) - ( 220 - x ) / 100 = 1/2
    ⇒ 5x - 4( 220 - x ) = 200
    ⇒ 9x = 1080
    ⇒ x = 120 km
    ∴ Required distance = 120 km


  1. X and Y are two station 500 km apart. A train start from X and moves toward Y at 20 km/hr another train station from Y at the same times and moves toward X at 30 km/hr. How far from X will they cross each other ?









  1. View Hint View Answer Discuss in Forum

    Suppose they meet x km. from X
    Then, x/20 = (500 - x)/30

    Correct Option: A

    Suppose they meet x km. from X
    Then, x/20 = (500 - x)/30
    ⇒ 30x = 10000 - 20x
    ∴ x = 200 km.



  1. 150 meter long train takes 10 second two pass a man who is going in same direction at the speed of 2 km/hr . What is the speed of the train ?









  1. View Hint View Answer Discuss in Forum

    Let the speed of the train be Y km/hr

    ∴ length of the train = 150 m
    = 150/1000 = 3/20 km.

    Time taken to cross the man = 10 seconds
    = 10/ (60 x 60) = 1/360 hrs .

    ∵ time = Length of the train /( speed of the train - speed of the man )
    ∴ 1/360 = ( 3 / 20) / ( Y - 2)

    Correct Option: B

    Let the speed of the train be Y km/hr

    ∴ length of the train = 150 m
    = 150/1000 = 3/20 km.

    Time taken to cross the man = 10 seconds
    = 10/ (60 x 60) = 1/360 hrs .

    ∵ time = Length of the train /( speed of the train - speed of the man )
    ∴ 1/360 = ( 3 / 20) / ( Y - 2)
    ⇒ (Y - 2 ) = 3/20 x 360
    ⇒ (Y - 2 )= 54
    ⇒ Y = 54 + 2
    = 56 km/hr.


  1. A train running at the speed of 45 kmph took 12 seconds in passing a certain point. Then the length of the train must be ?









  1. View Hint View Answer Discuss in Forum

    ∵ Speed = (45 x 5/18) = (25/2) m/sec
    Distance = (Time x Speed)

    Correct Option: C

    ∵ Speed = (45 x 5/18) = (25/2) m/sec
    Distance = (Time x Speed) = (12 x 25 / 2 ) meters
    = 150 meters

    ∴ Length of the train = 150 meters



  1. A train 75 meters long is running with a speed of 20 km/hr. It will pass a standing man in ?









  1. View Hint View Answer Discuss in Forum

    ∵ Speed of the train = (20 x 5/18) = (50/9) m/sec

    Correct Option: B

    ∵ Speed of the train = 20 x (5/18) = (50/9) m/sec
    ∴ Time taken by the train to pass the man = 75 x (9/50) = 13.5 sec