Dear Arnab,

I think it will be quite difficult to overcome your GMAT score for INSEAD and ISB relative to the applicant pools at these schools. While I do not have all of the relevant information, it seems your background and work experience puts you in a large subset of the applicant pool where the GMAT trends much higher. I would never go so far to say it is impossible to be admitted with your current score, but I do think your chances are low. Perhaps consider retaking to increase your quantitative score? INSEAD in particular looks for applicants to be in the 80% or better on both sections.

Good luck,
Lisa