Hello Aspirant,

See it is not percent, instead it must be percentile and percentile and percent are two different terms. If you get 80 percentile then it means that 84% candidates have scored equal to or less than your score in that shift.

Now it is not fixed that 80 percentile means 54 marks because it depends upon number of candidates appearing in that shift, difficulty level of paper and top score of that paper.

So sometimes it might be 54 marks and sometimes it might be 60 or sometime it might be 70 marks so it keeps on changing depending upon various factors.

You can check out marks Vs ranks Vs Percentile from the link given below :-

https://engineering.careers360.com/articles/jee-main-marks-vs-percentile

I hope this information helps you.

Good Luck!!