to redress the balance in the interest of statistical relevance (and the original post) the answer is 30
28: 44,870 votes
26: 532,475 votes
30: 60,095 votes
0: 800,597 votes
by the way, i read the question to a mathematical type friend and he said the answer was 0. so if its on paper you can get all clever clogs with it. if you process it at each stage you cant.
still sticking with 30 by the way and no you cant see my workings