Puzzles, Logic and inherently bad design
[All Ages Maths - Logic]
The question above seems simplistic, but I would like to stress that the model above is far from perfect as a tool for educating children.
To begin with, the first two lines form this axiomatic basis that the triangular and circular shapes possess some innate, inherent value to which we can all agree. However, it fails to account for all instances of the numbers possible: Suppose that the triangle assumes the value of (-5) as opposed to (5) alone; in which case, the possibility that one of the shapes having a negative value cannot be discounted.
In that case, the mathematically acceptable answers can, and must accept that ±50 and ±2 are legitimate answers, and that marking either of these wrong is the failure of the question setter in realising the complexity and depth of the question they themselves have set. This is merely an example of numbers from the Z set of integers, and we have yet to account for numbers from the Q, R or C sets where fractions and complex numbers enter the fray.
The lack of clarity at the very start of the question, opting to phrase the puzzle using "If you know that" instead of "Assuming only natural numbers" is a choice; and I argue that it is a terrible choice in how people of all ages are educated. Should the question setter not accept the negative values as possible answers, then it serves to stifle creativity. For the sake of the Singaporean youths, this type of logic puzzle cannot and must not substantiate.
It is bad enough that people do not take responsibility for the questions they create and set. Nothing has been done to force these corrections, and question setters continue to wield and tamper their social privileges carelessly. We must demand stricter measures to rectify these mistakes, or more children are going to find Maths difficult not because of the innate logic it proffers, but because people cannot define questions accurately and concisely.
I call upon all tuition centres, both our collaborators and competitors alike, to sound off and accuse the prevalence of bad puzzle designs before it costs human lives in the future.