Don't worry. I got a score of 122 in economic mathematics during the postgraduate entrance examination. It's not very high, but I'm satisfied. I use the line generation of Tongji Fourth Edition. I used the second edition at school, which is similar to the third edition. I bought the fourth edition myself later, and I felt that the thinking of the fourth edition was clearer, especially the part about rank and linear relationship was better understood, unlike the second edition, which was a bit confusing.