Two trains of lengths 120 m and 180 m are moving in the same direction at speeds of 60 km/h and 40 km/h, respectively. Find the time taken by the trains to cross each other.
54 seconds
Same direction, so relative speed: \(60-40=20\) km/h \(= \tfrac{50}{9}\) m/s.
Combined length of both trains: \(120+180=300\) m.
Time to cross: \(300 \div \tfrac{50}{9} = 300\times\tfrac{9}{50} = 54\) seconds.
Hence, the trains take 54 seconds to cross each other.
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