First of all, we should judge the conditions and see what mathematical conditions are given in the topic. For example, there are four conditions for this topic: 5 yuan with a triangular ruler, 2 yuan with an eraser, 8 yuan with a pen and 3 yuan with a notebook.

Second, if you want to think well, decide whether to ask an addition question, a subtraction question or a multiplication question. Of course, we can also ask a more complicated mathematical problem and perform mixed operations. Topics like this can generally ask some mathematical questions about spending money and price, which are also closely related to life.

Third, after thinking it over, write out the complete conditions and questions and answer them. One thing to note here: the questions raised should be reasonable; It is best to simply calculate the questions raised; The questions raised must meet the given conditions and cannot go beyond the scope.