I got74.77%in HSC from Maharashtra.i got phy.67chem.57,math76,eng.75.electronics-161/200, environment50/50,am I in top 20 percentile for OBC
For 2018 Maharashtra Board OBC Cutoff marks for top20 percentile category you need a total minimum of 355 marks across PCM and One Language and any one ither subject to be in top20 percentile and eligibility to IIT/NIT.
Since your total is way above yiu shallbe eligible for sure.
Yiur total is approximately 375 considering PCM and English and EVS.
EVs is Scaled upto 100marks for reference.