Tanmay, 

The criteria for 75% in 10+2 examination never drops.  It has remained same since year amd it will aslo be 75% this year. 

To qualify for NIT/IIIT/IIT you need to 75% in 10+2 or be in top 20 percentile of your respective board. Every year each board declare its top 20 percenrile cut off and if you are in top 20 percentile of your board then you will get admission in NIT/IIT/IIIT.

Maharashtra hsc board will declare its top 20 percentile before Josaa so don't worry.