Question
A train 525 meters long running at a speed of 103 kmph
overtakes another train which is 425 meters long running at a speed of 73 kmph in the same direction. Find the time taken by the faster train to overtake the slower train. (in seconds)Solution
Total distance = 525 + 425 = 950 m When trains running in the same direction, then their relative speed are the difference between their speeds ⇒  Net speed = 103 - 73 = 30 kmph ⇒  Speed in m/s = (5/18) x 30 = 25/3 m/s Total time = 950/(25/3) = 38 × 3 = 114 ∴  Time taken by the faster train to overtake the slower train = 114 sec
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