Let say 8th to 12th players are the last 5 and they lost their all matches except against each other. So 8th has to win or draw
(does not matter since total point would not change and I will go for win)
against 9,10,11 and 12th, 9th would win against 10,11,12th etc and lost against 8th. So The total point of the last 5 players would be 8,6,4,2 and 0 at worst. That makes total 20. So the first three, 1st, 2nd and 3rd has to have 60 point at least. This is only possible if 1st, 2nd and 3rd would win all matches against other players except the matches between them. They can draw or win against each other. The total point would be 60.
As a result,
4th, 5th, 6th, 7th games has to be lost against 1st, 2nd and 3rd. and win against 8th, 9th, 10th, 11th, 12th. In between 4th to 7th cannot be known and does not change the fact of the given in the question.
8th has to lose against 1st to 7th as mentioned before. and win against the rest to become 8th.