Hello Aspirant,
In order to get a call from IIMs CAT score is not the only parameter involved in the selection procedure. After CAT exam every IIM prepares a merit list to call students for next round of interview based on your aggregate score which comprises of many parameters such as CAT marks, 10th, 12th and graduation percentage, work experience etc.
To get a call from IIM Shillong you should have around Overall 95 CAT Percentile with 75 sectional cutoff as General Category so you should meet the cutoff to get into there.
You can also prefer the below given link to get more information about IIM Shillong admission.
https://bschool.careers360.com/articles/iim-shillong-admission-criteria
Good Luck!
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