Student who got 91.25% in 12th commerce without maths can get admission in du south campus under b.com pass under merit base
To get into DU the minimum percentage to qualify should be above 94%. Since enough have scored 91.25% it is difficult to get admission. Alternatively, you can try taking the DU entrance examination and take admission.
Also try our new college predictor link below :
https://engineering.careers360.com/jee-main-college-predictor
In top colleges like SRCC, Hindu College, St. Stephens, Ramjas College, Hansraj etc, chances are low as these colleges have cut offs in the 96%-99% range. In colleges like Acharya Narendra Dev College, Aryabhatta College, Deshbandhu college, Dr. Bhimrao Ambedkar College, Dyal Singh College, Motilal Nehru College, P. G. D. A. V college, Rajdhani college, Shivaji College, Shyam Lal College, Sri Aurobindo College (evening).
Do keep an eye on cut off of each rounds, in the later rounds the cut off goes lower.
I could not understand your point about merit base. If you could explain it in the comments below, I can help you better.
Hope this helped. Good luck.