Dear aspirant,
the percentile and marks relation varies fro exam to exam as well as from year to year. General trend is, for a certain percentile, required marks is getting higher each year. Percentile means you position, 47 percentile means, out of 100 students, your position 53rd, 99 percentile means positioned within top 1 percent.
Hope it helps.
All the best for your future endeavours!
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