CREATE TABLE table_54664 ("Home team" TEXT, "Home team score" TEXT, "Away team" TEXT, "Away team score" TEXT, "Venue" TEXT, "Crowd" FLOAT, "Date" TEXT)

When north melbourne played as the home team, what was the away team score?
SELECT "Away team score" FROM table_54664 WHERE "Home team" = 'north melbourne'
SELECT "Away team score" FROM "table_54664" WHERE "Home team" = 'north melbourne'