IIT Bombay anyhow has got a great reputation already along with great placements so choosing this college is the best option if you get a chance here. As far as I know, the assistant work you do in TA and RA at IIT Bombay is more or less same. However, RAs have to do more work compared to TAs (and hence they have stipend around 9-10K as against 8K for TA). The real difference is in duration of course. M Tech with TA-ship is 2 year program while in RA-ship its 3 year. Hence, cut-offs of TA are higher than RA.

Kindly refer to the link below to know the cutoffs of the same at IIT Bombay college.

https://www.google.co.in/amp/s/engineering.careers360.com/articles/gate-cutoff-for-iit-bombay%3famp

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