Via Wolfram Blog:
“The reason why that typical question is so dumbed down is that, without computers, it quickly becomes too hard to solve by hand. In an educational system geared to neat little hand-solvable problems, the only solution is to look at a toy version of the problem.
“One key conceptual problem shown here is that, in education, assumptions are usually instructions. Instead, we should be teaching students that assumptions (even implicit ones) are choices. Each should be considered for the impact that it might have on the validity of the solution.”