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> At 5pm a train departs from London going north at a constant speed of 100 miles per hour, at 6pm another train departs London going north at a constant speed of 20 miles per hour. Assuming the trains will go straight from their starting position, When will the the trains meet again?
> Your Answer (INCORRECT) : They will not meet again because the first train is faster than the second
> Correct answer : 12 days , 23 hours, 16 minutes, 5 seconds, and 750.4 milliseconds. The earth's circumference is 24901.461 miles. Since the train starts going north and is going straight through its entire journey, it must travel the entire diameter of the earth after 249.01461 hours. In this time the other train will have traveled 4980.2922 miles from the starting position. Solve when the trains will meet with after the first train goes around the entire earth: 20x + 4980.2922 = 100x , 80x = 4980.2922 , x = 62.2536525 hours needed to catch up after the first loop. Add the two measurements together to get the final time 249.01461 + 62.2536525 = 311.2682625 hours, or 12 days , 23 hours, 16 minutes, 5 seconds, and 750.4 milliseconds.
