Top 20 percentile cut-off marks of gujarat board 2016 is out of 500 or 650?

@ dipesh 
its out of 500 as the best 5 subject will be taken for the calculation of percentile . 
but there are certain rule for percentile , as if u will put maths in 6^th optional , then also , it will be calculated towards the percentile . 
the counting will be 3 subject compulsory – PCM and one common language subject ( english or hindi ) and 1 optional subject acc to your score . 
so, it will be from 500 . 
HOPE IT HELPS 
ALL THE BEST ..