New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    Train A running at speed of 72 km/hr crosses a platform

    having twice the length of train in 18 sec. Train B whose length is 300m crosses same platform in 27 sec, then find the speed of train B ?
    A 72 km/hr Correct Answer Incorrect Answer
    B 108 km/hr Correct Answer Incorrect Answer
    C 75 km/hr Correct Answer Incorrect Answer
    D 144 km/hr Correct Answer Incorrect Answer
    E 54 km/hr Correct Answer Incorrect Answer

    Solution

    Let length of train A = x Length of platform = 2x Speed = distance/time ⇒ 72 x 5/18 = (x + 2x)/18 ⇒ x = 120 m = length of train A Length of platform = 120 x 2 = 240m For train B, Speed = distance/time ⇒ (240 + 300)/27 x (18/5) ⇒ 72 km/hr

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