Greenhaus Education and Other "Effects"

My daughter sent me this article, Parents are Freaking Out Because They Can't Answer a 7-year Olds Exam Question,  the other day concerning a Twitter posting about a math problem that was frustrating students, parents, and lots of people on Twitter obviously. Here's the problem: The issue is there are two answers that could be correct: 65, if you use the 'work backwards' method, subtracting out the 17 that just got on from the 63 and then adding back the 19 that got off.  The other answer is 46, which results from simply subtracting out the 17 that just got on from the 63 currently on the train.  The teachers exam rubric/'test key" stated the correct answer as 46.  Hence - all the confusion, because that would mean the 19 was an unneeded number. The real problem here, and it is NOT an isolated situation, is that this question is very poorly worded, and thus open to both interpretations. The work-backwards approach assumes that the question is asking