The reasons why the score of engineering management major in Inner Mongolia University of Technology is lower than the national line are as follows:

1. The competition of this major in this school is relatively low, resulting in the enrollment plan not being full, so the score is relatively low.

2. The school hopes to attract more outstanding students by lowering the score line, and improve its popularity and reputation.

3. The school has set up a certain number of independent enrollment places in the enrollment plan of this major, which will leave room for candidates with low scores but special talents or achievements.

4. The national line is ranked according to the scores of national candidates. Different schools and majors will have different standards and priorities when choosing candidates, so the scores will be different.