I'm prob. going to get attacked for saying this, but yes you will get into schools with lower #s than white students if you're a minority. That's just how it is. I'm not going to make a normative argument as to how smart admitted black students are vis a vis white ones, or the merits of AA, but it seems disingenous to beat around the bush and say things like "it depends" and "you can't be sure." I'm not sure why there are so many AA supporters who like to pretend that AA doesn't exist, or that all the black students who get in with numbers that are below their school's medians were accepted because of their "soft factors." It just seems like BS to me. I'm a very ardent supporter of affirmative action, but it's really dishonest to try to avoid telling someone who's ignorant about the process that black students are simply accepted with lower #s than are their white counterparts. This doesn't mean that they are any less smart or qualified but lower #s they do have.
That said, you should do the best you can do. It's ridiculous to not work hard because you think you can coast along on AA.