Let me figure out this one... It can be something like this:
Say the West Midlands teams are an association and the Northwest teams are another association. A West Midlands team plays a Northwest team. Say West Brom win against Everton, Wolves draw against ManU, Aston Villa lose against ManCity and Birmingham lose against Liverpool.
So West Midlands team have 3(WBA)+1(Wolves)=4 points.
Northwest team have 1(MUFC)+3(MCFC)+3(LFC)=7 points. So the Northwest association win the tie.