Speed, Time and Distance


  1. A train travelling with uniform speed crosses two bridges of lengths 300 m and 240 m in 21
    seconds and 18 seconds respectively. The speed of the train is :
    1. 72 km/hr
    2. 68 km/hr
    3. 65 km/hr
    4. 60 km/hr

  1. View Hint View Answer Discuss in Forum

    Let the length of the train be x.

    ∴  Speed of the train =
    x + 300
    =
    x + 240
    2118

    ⇒ 
    x + 300
    =
    x + 240
    76

    ⇒  7x + 1680 = 6x + 1800
    ⇒  x = 120
    ∴  Speed of the train =
    x + 300
    =
    420
    = 20 m/sec
    2121

    =
    20 × 18
    kmph = 72 kmph
    5

    Correct Option: A

    Let the length of the train be x.

    ∴  Speed of the train =
    x + 300
    =
    x + 240
    2118

    ⇒ 
    x + 300
    =
    x + 240
    76

    ⇒  7x + 1680 = 6x + 1800
    ⇒  x = 120
    ∴  Speed of the train =
    x + 300
    =
    420
    = 20 m/sec
    2121

    =
    20 × 18
    kmph = 72 kmph
    5


  1. A train, with a uniform speed, crosses a platform, 162 metres long, in 18 seconds and another platform, 120 metres long, in 15 seconds. The speed of the train is
    1. 14 km/hr
    2. 42 km/hr
    3. 50.4 km/hr
    4. 67.2 km/hr

  1. View Hint View Answer Discuss in Forum

    Let the Length of the train be x

    Then, 
    x + 162
    =
    x + 120
    1815

    (Speed of the train)
    ⇒ 
    x + 162
    =
    x + 120
    65

    ⇒  6x + 720 = 5x + 810
    ⇒  x = 810 – 720 = 90
    ∴  Speed of the train =
    90 + 162
    m/sec.
    18

    =
    252
    ×
    18
    kmph
    185

    = 50.4 kmph

    Correct Option: C

    Let the Length of the train be x

    Then, 
    x + 162
    =
    x + 120
    1815

    (Speed of the train)
    ⇒ 
    x + 162
    =
    x + 120
    65

    ⇒  6x + 720 = 5x + 810
    ⇒  x = 810 – 720 = 90
    ∴  Speed of the train =
    90 + 162
    m/sec.
    18

    =
    252
    ×
    18
    kmph
    185

    = 50.4 kmph



  1. A train with a uniform speed passes a platform, 122 metres long, in 17 seconds and a bridge, 210 metres long, in 25 seconds. The speed of the train is
    1. 46.5 km/hour
    2. 37.5 km/hour
    3. 37.6 km/hour
    4. 39.6 km/hour

  1. View Hint View Answer Discuss in Forum

    Let the length of the train be x
    According to the question,

    x + 122
    =
    x + 210
    1725

    ⇒  25x + 3050 = 17x + 3570
    ⇒  25x – 17x = 3570 – 3050
    ⇒  8x = 520
    ⇒  x =
    520
    = 65 metres
    8

    ∴  Speed of the train =
    65 + 122
    17

    =
    187
    metre/second
    17

    = 11 metre/second
    =
    11 × 18
    kmph
    5

    = 39.6 kmph

    Correct Option: D

    Let the length of the train be x
    According to the question,

    x + 122
    =
    x + 210
    1725

    ⇒  25x + 3050 = 17x + 3570
    ⇒  25x – 17x = 3570 – 3050
    ⇒  8x = 520
    ⇒  x =
    520
    = 65 metres
    8

    ∴  Speed of the train =
    65 + 122
    17

    =
    187
    metre/second
    17

    = 11 metre/second
    =
    11 × 18
    kmph
    5

    = 39.6 kmph


  1. A train travelling at a speed of 30 m/sec crosses a platform, 600 metres long, in 30 seconds. The length (in metres) of train is
    1. 120
    2. 150
    3. 200
    4. 300

  1. View Hint View Answer Discuss in Forum

    Let the length of train be x
    According to the question,

    x + 600
    = 30
    30

    ⇒  x + 600 = 900
    ⇒  x = 900 – 600 = 300 m

    Correct Option: D

    Let the length of train be x
    According to the question,

    x + 600
    = 30
    30

    ⇒  x + 600 = 900
    ⇒  x = 900 – 600 = 300 m



  1. A 120 metre long train is running at a speed of 90 km per hour. It will cross a railway platform 230 m long in :
    1. 4
      4
      seconds
      5
    2. 9
      1
      seconds
      5
    3. 7 seconds
    4. 14 seconds

  1. View Hint View Answer Discuss in Forum

    Speed of train = 90 kmph

    = 90 ×
    5
    = 25 m/sec
    18

    Distance covered
    = 230 + 120 = 350 m
    ∴  Time taken =
    350
    = 14 seconds
    25

    Correct Option: D

    Speed of train = 90 kmph

    = 90 ×
    5
    = 25 m/sec
    18

    Distance covered
    = 230 + 120 = 350 m
    ∴  Time taken =
    350
    = 14 seconds
    25