Speed, Time and Distance


  1. A car travels 80 km. in 2 hours and a train travels 180 km. in 3 hours. The ratio of the speed of the car to that of the train is :









  1. View Hint View Answer Discuss in Forum

    Speed =
    Distance
    Time

    ∴  Speed of car : Speed of train
    =
    80
    :
    180
    = 40 : 60 = 2 : 3
    23

    Correct Option: A

    Speed =
    Distance
    Time

    ∴  Speed of car : Speed of train
    =
    80
    :
    180
    = 40 : 60 = 2 : 3
    23


  1. Two trains of equal length are running on parallel lines in the same direction at 46 km/h and 36 km/h. The faster train passes, the slower train in 36 seconds. The length of each train is :









  1. View Hint View Answer Discuss in Forum

    Let the length of each train be x metre.
    Relative speed = 46 – 36 = 10 kmph

    =
    10 × 5
    metre/second
    18

    =
    25
    metre/second
    9

    ∴  
    2x
    = 36
    (25/9)

    ⇒  2x =
    36 × 25
    = 100
    9

    ⇒  x = 50 metre

    Correct Option: B

    Let the length of each train be x metre.
    Relative speed = 46 – 36 = 10 kmph

    =
    10 × 5
    metre/second
    18

    =
    25
    metre/second
    9

    ∴  
    2x
    = 36
    (25/9)

    ⇒  2x =
    36 × 25
    = 100
    9

    ⇒  x = 50 metre



  1. Two trains start from a certain place on two parallel tracks in the same direction. The speed of the trains are 45 km/hr and 40 km/hr respectively. The distance between the two trains after 45 minutes will be









  1. View Hint View Answer Discuss in Forum

    Relative speed = 45– 40 = 5 kmph

    ∴  Required distance = 5 ×
    45
    km
    60

    =
    15
    km = 3 km 750
    4

    Correct Option: C

    Relative speed = 45– 40 = 5 kmph

    ∴  Required distance = 5 ×
    45
    km
    60

    =
    15
    km = 3 km 750
    4


  1. A boy started from his house by bicycle at 10 a.m. at a speed of 12 km per hour. His elder brother started after 1 hr 15 mins by scooter along the same path and caught him at 1.30 p.m. The speed of the scooter will be (in km/hr)









  1. View Hint View Answer Discuss in Forum

    Let the speed of Scooter be x Distance covered by cycling in

    3
    1
    hours = Distance covered by scooter in
    2

    2
    1
    hours
    4

    ⇒  12 ×
    7
    = x ×
    9
    24

    ⇒  x =
    12 × 7 × 2
    9

    =
    56
    = 18
    2
    kmph
    33

    Correct Option: C

    Let the speed of Scooter be x Distance covered by cycling in

    3
    1
    hours = Distance covered by scooter in
    2

    2
    1
    hours
    4

    ⇒  12 ×
    7
    = x ×
    9
    24

    ⇒  x =
    12 × 7 × 2
    9

    =
    56
    = 18
    2
    kmph
    33



  1. A policeman goes after a thief who has 100 metres start, if the policeman runs a kilometre in 8 min, and the thief a km in 10 min, the distance covered by thief before he is over-powered is









  1. View Hint View Answer Discuss in Forum

    Relative speed =
    1000
    1000
    810

    =
    5000 − 4000
    =
    1000
    m/minute
    4040

    ∴  Required time =
    100
    1000
    40

    =
    4000
    = 4 m/minute
    1000

    ∴   Distance covered by the thief =
    1000
    × 4
    10

    = 400 metres

    Correct Option: B

    Relative speed =
    1000
    1000
    810

    =
    5000 − 4000
    =
    1000
    m/minute
    4040

    ∴  Required time =
    100
    1000
    40

    =
    4000
    = 4 m/minute
    1000

    ∴   Distance covered by the thief =
    1000
    × 4
    10

    = 400 metres