over/under win totals question

[unstandable]

I apologize if this has been answered elsewhere, but I couldn't find anything on a search.

I was looking at some NBA regular season win total over/unders. For example, here is Chicago:

Over 41 (-125)
Under 41 (-105)

Since -125 doesn't match -105, is there a way to calculate the number of wins the Bookmaker actually expects - it seems like it can't really be exactly 41.

Thanks.

[shantystar]

its ok pally!

[Bread]

[skrtelfan]

Normalize it to remove the juice and then put it into a poisson-based season-wins estimate. The vig-free line there is approximately ov41 -109/un41 +109, which poisson tells us is about the same as 41.23 wins.