Carcass wrote:
The school bus always stops at the railroad tracks. When the warning light is not flashing, it then proceeds directly across if the tracks are clear. However, when the warning light is not flashing and the tracks are not clear, the school bus, waits until they are clear and then proceeds
immediately across them.
If the statements above are true and it is true that the school bus stops at the tracks and then does not proceed to cross them, which of the following must also be true?
(A) The warning light is flashing and the tracks are clear.
(B) The warning light is flashing and the tracks are not clear.
(C) The warning light is not flashing and the tracks are not clear.
(D) The warning light is flashing, or the tracks are not clear, or both.
(E) The warning light is not flashing, or the tracks are not clear, or both.
NO LIGHT + TRACK CLEAR = MOVES
NO LIGHT + TRACK N.CLEAR = D.MOVE
From here, all I could conclude was that when the track is not clear, the train does not move (based on no warning lights).
Why is the answer not "C"? Are we to assume that those conditions are the ONLY cases where the train would move and not move? How can we know for certain that the light does not have an effect on whether or not the train stops? Not to be facetious, but what if the light is on and the track is clear, the train also does not move? Is it not also possible, since we do not know the conditions of the warning light being on, that the opposite can happen? It might not sound too great but, at face value, there seems to be room for interpretation for the average skeptic. Please help!