10 points for 1st, 7.5 points for 2nd, 5 points for 3rd.

Once you do that you would add the unitab divi to the score so for instance Mr. Celebrity paid 6.50 for the win and 2.10 for the place so he would get 8.60 points from that plus the 10 points for being the winner meaning he scores 18.60 points all up.