# Voting Question: 5/6th of the way across a narrow railroad bridge, Anoop hears a train coming towards him. He knows that the tr?

• Voting Question: 5/6th of the way across a narrow railroad bridge, Anoop hears a train coming towards him. He knows that the tr?

Answer #1 | 18/12 2013 03:12
There is insufficient information to answer the question - we don't know how long the bridge is; although we know that the train is coming towards him, but we don't know from which direction. Apart from anything else, the fact that a train is involved is irrelevant - the answer will be the same if it was a car, cyclist or escaped lion that was coming towards him.
Answer #2 | 18/12 2013 22:42
Actually, there IS sufficient information to answer this. Anoop can either run towards the oncoming train and just escape it at the end of the bridge, or run away and just escape it at the start of the bridge. Although neither the length of the bridge (B) nor the train's distance from it (D) are given, there is enough information to calculate that D=B/4 and that Anoop's running speed is 23.33 mph (two thirds of the train's speed). If he runs forward, he covers 1/6 of the length B in the same time as the train covers 1/4 of the length; if he runs back, he covers 5/6 of the length B in the same time as the train covers 5/4 of the length. What is unclear is HOW Anoop knows where the train is when he hears it!