Hello Sumit,
I would sa that you should choose between IIIT Bhagalpur ECE and IIIT Manipur ECE. I would not recommend choosing Mechatronics branch as it is a relatively new branch and hence the career options inside India are lesser as compared to ECE which is one of the most dynamic branches in terms of placements.
As for average salary, IIIT Bhagalpur was established in 2017 and Manipur in 2015, so neither of the institutes has any passout batch and hence the average salary can't be given yet.
For fee, the 4 year tution fee of IIIT Bhagalpur is Rs. 8 lakhs and that of IIIT Manipur is Rs.7.4 lakhs,so not much difference.
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