Hi Aspirant,
The most basic eligibility criteria to appear for CAT is that you need to have a graduate degree or you must be in the final year of graduation.
Also, you must score more than 50% marks.
As far as IIM's are concerned,each and every IIM has its different set of cutoff and requirement set.
Try to score very high marks in CAT which shall prove to be the deciding factor.
Hope this helps.

IIM Shillong

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