So, the issue I am trying to raise is not at all with whether what mongo intends to say about decimal numbers is correct. You surely know this area, far better than I. It is about how the question is worded, when it would be so easy to change the wording so that people who were precise about language could get it right. True/false questions especially need precise statements. Framing questions, and the theory of strings, are things where I do have a large body of knowledge and experience.
As for a wholistic approach, I can try to squint and think only vaguely about what the question means, and thus have it more likely that I am guessing the answer you guys have in mind. Or I can think more like a json validator, which would not hesitate to say there is no ‘decimal number’ datatype. Is it not computer science we are talking about? Why not adjust some of the questiosn to make them more precisely true or false?
Wm