Hello 

there is no entrance for bsc maths hons in DELHI UNIVERSITY.The admission will be based on the 12th marks. Minimum eligibility criteria is  50% in maths And 45 % in qulifying examinatiom ie 12th std overall %. The merit shall be determined on the basis of  one language mathematics and two best academic subjects.

For more details refer the following link

https://university.careers360.com/articles/du-eligibility-criteria

Hope this helps you