The CNN program here
reports that over 500 students at the University of Utah have concealed carry permits. I assume that there are probably about 30,000 students on campus. If that number is correct, that is only about 1.6 percent of the students being able to carry a gun. It would be nice to get that number somewhat higher. Still, 500 on students on campus must mean that there will often be multiple people around the school who are able to stop an attack. I would be willing to bet that there won't be any significant multiple victim public shootings at that university.
One professor, Barbara Nash, who is interviewed claimed that the idea that more guns would mean a safer place is a "stupid" idea. It would have been nice if the professor could have pointed to some evidence that students with a concealed handgun permit posed a danger. On the other hand, another professor in the Business School, Randall Boyle, said he actually felt safer now that some students in the class legally have concealed handguns.