How many cut off are necessary for jee advanced

There is no fixed cutoff of jee advanced as the paper pattern even comes to know on the day of exam while you would be starting to attempt it. Every year total marks of paper 1 +paper 2 varies every year like last year it was 366. In 2k16 it was 372 while in 2k11 i guess it was 544. So focus on concepts and dont worry on cutoff. Having clear concepts would fetch you a good rank and thereby a good college.