If you have something to do, you must take a closer look. Primary school mathematics is relatively simple, especially multiple-choice questions and fill-in-the-blank questions.
The difficulty is to cover the original answer with a piece of draft paper for the last few times and recalculate it on the draft paper.
Especially in calculation and application, you can't lose points. Check the calculation first, then the application, and then the multiple-choice question. Don't dwell on this topic. It's not worth losing the previous 95 points for the last 5 points.
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