The 2019 cut off for the Bachelor of Management Studies (BMS) course at Guru Nanak College of Arts, Sciences and Commerce (GNCSAC), Mumbai was around 69%. Based on this, you will be able to secure admission to the college with 80% Class 12th marks. However, please note that the cut off depends on multiple factors and since this years CBSE results have been influenced by exam cancellation, the cut off might vary.
Hence, you should also consider applying to other BMS colleges in Mumbai to have a safety net. Here are some other colleges that you can consider.