Disparity in the NBA

I never watch ESPN and seldom read the sports page, so it's likely that the NBA happenings that are news to me aren't news to some of you: the worst team in the Midwestern division has the same record as the best team in the Atlantic division. Both Utah and Philadelphia are 6-6. That's even more remarkable when you remember that teams play about 70% of games within their conference (I don't how know the ratio for either team at this stage).

I just noticed another stat, the record of Western conference teams against the Eastern conference: 45-24. With the mechanisms the NBA uses to achieve parity, a disparate record like that is unusual. What are the odds of flipping 45 heads in 69 coin tosses? Is the sample size large enough to be meaningful yet? (I don't have my college statistics text with me and don't remember how to calculate this without referencing my book). It will be interesting to see how long the nearly 2:1 ratio lasts.