SQL Server version numbers, when related to hotfixes, are they "inclusive"?
Unless you have access to the log files for every cumulative update install, the only thing you would know is #3:


  Hotfix 9.00.3182 has definitely been applied, there simply isn't enough information available to determine if the other 2 have been applied or not.


Cumulative updates are, well, cumulative. So are the builds within a CU branch. So 9.00.3182 will contain the fixes from 3179, 3178, 3165, 3122, 3068, etc. Microsoft used to release certain critical fixes individually, but now they have almost completely stopped doing that, opting for a ~60 day Cumulative Update delivery model (security fixes excepted).

The challenge comes when you pass a service pack boundary. There are cases where a fix is released in a cumulative update right before a service pack is released. The service pack code path was frozen at least 60 days earlier (since SPs go through more rigorous testing/regression etc). So, the service pack - even though released later - is missing fixes that won't be in that branch until the first cumulative update for that service pack. This is why you will often see a CU released out of band, almost immediately after a service pack is released.

Then, of course, there is the situation where multiple branches are being maintained, and multiple CUs come out for the lower service pack. There will be fixes there which weren't even known issues when the newer service pack was released.

This means that in many cases a newer build (say, 2005 SP4, 9.00.5000) is missing fixes from cumulative updates for SP3 (say, CU15, which was released several months after SP4). All of those fixes are usually also available in subsequent CUs for the later service pack, but just looking at version number alone wouldn't really tell you that unless you knew which fixes you are trying cross-reference. You'd need a database for that, not a numeric/string compare.

You're kind of playing with fire here, anyway. You're running SQL Server 2005, and not even on the most recent service pack. Unless you have gone through extended support, you are completely on your own. In fact 2008 and 2008 R2 both hit end of mainstream support in about 60 days.

My philosophy is to always be on the absolute latest service pack for any version I am running, and unless there is something prohibitive, always be on the latest CU for that service pack as well. So, rather than worry about whether the fixes for 3179 or 3178 were installed independently, I'd focus more on getting onto a more modern build (SP4 + MS12-070, putting you at 9.00.5324), or a more modern version (and one that isn't about to sunset).