Big Jim, engineer of the Oval Express says: "We blew off a cylinder head an hour after leaving the station and had to continue the trip at three-fifths of the former speed, which brought us in two...

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Extracted text: Big Jim, engineer of the Oval Express says: "We blew off a cylinder head an hour after leaving the station and had to continue the trip at three-fifths of the former speed, which brought us in two hours late. If the accident had occurred fifty miles farther on, the train would have arrived forty minutes sooner". How long was the run between stations? Note: I only know the final answer but not sure how to get it and the steps involved to work it out. So, please show all working step by step by explaining each of your steps, thanks for your assistance!