Admission in NIT is based on your JEE Mains Rank and percentile its does not have to do anything with Advance.Advance is for IITs,RGIPT,IISc Banglore.
If you get good rank in Mains then only you will get the Top NITs. And if you have have good marks in Advance then you will get admission in IITs or top government colleges.
Hope this will help you,please feel free to ask if you have any further queries.
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