It will depend of different factors like distribution, density, AP mounting location, etc, but usually in hospitality models like R320 and H320 will do the job. It is still recommended to do a survey and test if these AP models will cover all your needs.
Hi Lilia, For predictive surveys there are many tools that help for that purpose, some of them a little pricy. Usually the best recommendation tends to be Ekahau, Airmagnet, also Tamograph do the job and is less expensive but with some features missing though.
If the dormitories layout is similar in all of them, it could be very helpful to just take one AP model and to coverage tests in a couple of rooms, that way you can have no predictive but real tests, and the results you have of these tests can be of great help for your design.
just adding that for dorms, H320 / H510 can be really nice since you get "user accessible" network jacks which can still be authenticated against radius / etc.. And if the building is drywall, you can cover the same room + the adjacent rooms almost for sure.
Otherwise, I've used R310 extensively and they've proven to be extremely reliable. R320s are a bit newer but so far no issues