To get into IIT Bombay CSE you need to get rank Under 50. This rank is possible if one score around 300 out of 360 If JEE advance is off 360 marks let. Now the last ranker which gets into IIT Bombay is 2000. SO you really need to work hard to make it.

It can't be predicted because selection depends on rank and rank varies according to the number of applicants and toughness of question paper

Cutoff rnaks will vary for all branches, Quotas and Category in IIT BOmbay under Jee Advanced marks. 

Cutoff for all branches sharedbelow. 

https://engineering.careers360.com/articles/jee-advanced-cutoff-for-iit-bombay/amp