A mile-long train is traveling from southeast to northwest at 62 miles per hour.
Some old guy is driving a van south to north at 57 miles per hour on a highway that intersects the railroad.
The van is 1.5 miles away when the middle of the train is at the crossing.
Will the train have passed the crossing by the time the van arrives, or will the van need to stop and wait? If the latter, how long?
[All the numbers above, except the van speed, are guesses, so even if you know how to structure the equation and how to solve it, you probably won’t get the actual answer. Though you could probably start with the answer and figure out what the other actual numbers could’ve been.]
The actual, real-life answer: If there hadn’t already been two vehicles waiting at the crossing, the end of the train would’ve just passed and the gate would be going up so that the van could have continued without stopping. Just barely.