Personal Comment: This is a distance, speed, etc. type problem.
The Genius and the Train Enigma!
What we know: A genius came to a narrow railroad bridge and began to run across it. He had crossed 3/8 of the distance when a whistle behind him warned of an approaching train. Being a genius, he instantly evaluated his alternatives. If he were to run back to the beginning of the bridge at his speed of 10 mph, he would leave the bride at precisely the moment the train entered it. If he kept on running to the end of the bridge,
the train would reach him just as he left the bridge.
