it's just asking you what group wins the majority (aka most of the votes) on a law, out of 10 votes.
for example, say you have a group voting on whether or not a club should get shirts made. 6 people say YES SHIRTS and 4 people say NO THAT IDEA SUCKS.
the YES SHIRTS group won the vote by a margin of 2, because 2 more people voted for shirts than the amount of people who think shirts suck. it's asking you what most of the group in your question agreed on.