1. Answer: Option (C) 36 sec Explanation: Speed of train relative to jogger = (45 - 9) km/hr = 36 km/hr. = 36 x (5 /18)m/sec = 10 m/sec. Distance to be covered = (240 + 120) m = 360 m. Time taken = 360/10 sec = 36 sec.

    Answer: Option (C) 36 sec
    Explanation:
    Speed of train relative to jogger = (45 – 9) km/hr = 36 km/hr.

    = 36 x (5 /18)m/sec
    = 10 m/sec.

    Distance to be covered = (240 + 120) m = 360 m.

    Time taken = 360/10 sec = 36 sec.

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  2. Answer: Option (C) 48 Explanation: Relative speed = (60+ 90) km/hr = 150 x (5/18) m/sec = 125/3 m/sec. Distance covered = (1.10 + 0.9) km = 2 km = 2000 m. Required time = 2000 x (3/125) sec = 48 sec.

    Answer: Option (C) 48
    Explanation:
    Relative speed = (60+ 90) km/hr

    = 150 x (5/18) m/sec
    = 125/3 m/sec.
    Distance covered = (1.10 + 0.9) km = 2 km = 2000 m.

    Required time = 2000 x (3/125) sec = 48 sec.

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  3. Answer: Option (A) 40 sec Explanation: Formula for converting from km/hr to m/s: X km/hr = X x (5/18) m/s. Therefore, Speed = 45 x (5/18) m/sec = 25/2 m/sec. Total distance to be covered = (360 + 140) m = 500 m. Formula for finding Time = Distance/Speed Required time = (500 x 2)/25 sec = 40 sec.

    Answer: Option (A) 40 sec
    Explanation:
    Formula for converting from km/hr to m/s: X km/hr = X x (5/18) m/s.
    Therefore, Speed = 45 x (5/18) m/sec = 25/2 m/sec.
    Total distance to be covered = (360 + 140) m = 500 m.

    Formula for finding Time = Distance/Speed

    Required time = (500 x 2)/25 sec = 40 sec.

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  4. Answer: Option (A) 50 m Explanation: Let the length of each train be x metres. Then, distance covered = 2x metres. Relative speed = (46 - 36) km/hr = 10 x (5 /18)m/sec = 25/9 m/sec 2x/36 = 25/9 2x = 100 x = 50.

    Answer: Option (A) 50 m
    Explanation:
    Let the length of each train be x metres.

    Then, distance covered = 2x metres.

    Relative speed = (46 – 36) km/hr

    = 10 x (5 /18)m/sec

    = 25/9 m/sec

    2x/36 = 25/9

    2x = 100

    x = 50.

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  5. Answer: Option (B) 89 sec Explanation: Speed = (240/24) m/sec = 10 m/sec. Required time = (240 + 650)/10 sec = 89 sec.

    Answer: Option (B) 89 sec
    Explanation:
    Speed = (240/24) m/sec = 10 m/sec.
    Required time = (240 + 650)/10 sec = 89 sec.

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  6. Answer: Option (B) 3 : 2 Explanation: Let the speeds of the two trains be x m/sec and y m/sec respectively. Then, length of the first train = 27x metres, and length of the second train = 17y metres. (27x + 17y) /(x+ y)= 23 27x + 17y = 23x + 23y 4x = 6y x /y= 3/2 .

    Answer: Option (B) 3 : 2
    Explanation:
    Let the speeds of the two trains be x m/sec and y m/sec respectively.
    Then, length of the first train = 27x metres,
    and length of the second train = 17y metres.
    (27x + 17y) /(x+ y)= 23
    27x + 17y = 23x + 23y
    4x = 6y
    x /y= 3/2 .

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  7. Answer: Option (C) 245 m Explanation: Speed = 45 x 5 m/sec = 25 m/sec. 18 2 Time = 30 sec. Let the length of bridge be x metres. Then, 130 + x = 25 30 2 2(130 + x) = 750 x = 245 m.

    Answer: Option (C) 245 m
    Explanation:
    Speed = 45 x 5 m/sec = 25 m/sec.
    18 2
    Time = 30 sec.

    Let the length of bridge be x metres.

    Then, 130 + x = 25
    30 2
    2(130 + x) = 750

    x = 245 m.

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  8. Answer: Option (B) 50 km/hr Explanation: Speed of the train relative to man = 125 m/sec 10 = 25 m/sec. 2 = 25 x 18 km/hr 2 5 = 45 km/hr. Let the speed of the train be x km/hr. Then, relative speed = (x - 5) km/hr. x - 5 = 45 x = 50 km/hr.

    Answer: Option (B) 50 km/hr
    Explanation:
    Speed of the train relative to man = 125 m/sec
    10
    = 25 m/sec.
    2
    = 25 x 18 km/hr
    2 5
    = 45 km/hr.

    Let the speed of the train be x km/hr. Then, relative speed = (x – 5) km/hr.

    x – 5 = 45 x = 50 km/hr.

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  9. Answer: Option (D) 150 metres Explanation: Speed = 60 x 5 m/sec = 50 m/sec. 18 3 Length of the train = (Speed x Time). Length of the train = 50 x 9 m = 150 m.

    Answer: Option (D) 150 metres
    Explanation:
    Speed = 60 x 5 m/sec = 50 m/sec.
    18 3
    Length of the train = (Speed x Time).

    Length of the train = 50 x 9 m = 150 m.

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  10. This answer was edited.

    Answer: Option B  Explanation:Speed = 54 x (5/18) m/sec = 15 m/sec.Length of the train = (15 x 20)m = 300 m. Let the length of the platform be x metres. Then, (x + 300)/36 = 15x + 300 = 540 x = 240 m.

    Answer: Option B 

    Explanation:
    Speed = 54 x (5/18) m/sec = 15 m/sec.
    Length of the train = (15 x 20)m = 300 m.

    Let the length of the platform be x metres.

    Then, (x + 300)/36 = 15
    x + 300 = 540

    x = 240 m.

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