If an electric train is traveling east at 70 mph and the wind is blowing west at 20 mph, in which direction does the smoke blow?
Let's analyze the information given:

1. The train is an electric train.
2. Electric trains do not produce smoke as they don't rely on combustion engines for power.

Therefore, the question is a trick question because there is no smoke produced by an electric train.

Final answer: There is no smoke.