Each of the Texas schools interviews approximately 300 applicants, and they fill their classes with about 100 students. So going off of statistics alone, you have roughly a 1 in 3 shot of matriculating at a particular school after interviewing there. Now, not everyone who is accepted ends up attending that school, so your odds of getting accepted are actually a bit higher.
That being said, those odds are entirely theoretical. In reality, whether or not you get in depends largely on your performance during the interview. That's why nobody here can accurately tell you what your chances are, but I would venture to say that you've got a pretty decent shot just from interviewing. Focus your efforts on doing well, and have confidence in your chances. Good luck on your interview.