Honestly, the stream through which you complete your graduation hardly matters in the term of the selection process of any b-school. What matters is how much percentage you scored in all your academic records starting from 10th, 12th and graduation. Even if you are doing dual degree then you need to show the score of the dual degree. 50% of all your academic records are essential criteria for your eligibility to sit in most of the MBA exams.

After you giver CAT exam then all the colleges in which you apply including IIMs makes a merit list to call students for second round of interview and WSAT which is made in the basis of your aggregate score and which is based on different parameters such as CAT marks, 10th, 12th and graduation percentage, work experience, engineer or non-engineer, gender etc. whose weightage vary according to different colleges. In this, your academic percentage generally has a weightage of 10-25% so that makes a big difference in your merit rank.

So, don't worry about your stream but work hard to get good percentile in MBA exams and also maintain a good percentage of your graduations.

All the best!!