Kolkata

Lateral entry in diploma is only possible in second year, not in the third year and is completely dependent on college and university norms, some university allow it and some won't plus you need to have good scores in first year to apply for the same. For further details contact the college authorities.
Details: https://www.shiksha.com/engineering/course/diploma-in-mechanical-engineering-lateral-entry-chandigarh-college-of-engineering-and-technology-289459

I guess, this might help you:
http://su.onlineadmission.org/ghc/coursesoffer.aspx?clgcode=APCC

Hi,
The timings are from 10:00 AM to 2:00 PM (time slots have already been allotted). Please refer to the merit list.

You could apply for MA Economics or M.Sc Economics/statistics.
Or, you may also go for MBA.
Apart from this, you can pursue CFA.
Jobs scope could range from bank jobs to data analytics to Policy making.

These are some of the colleges for mathematics honours:
*Maulana Azad College
*Vidyasagar College
*Sammilani Mahavidyalaya
*Purash Kanpur Haridas Nandi Mahavidyalaya
*Charu Chandra College
*Mahadevananda Mahavidyalaya.

Hi Kamlesh, The last date to apply is 15th July.

For admission in Amity University, Kolkata, you will have to apply online. The application fees is Rs.1100 payable online only. Then after counselling, if selected, on the admission day, you will have to submit a demand draft. The DD should carry around Rs.40 -50 thousand (tentatively) which will be the fees for the first semester.