There are 13-8 = <<13-8=5>>5 rooms with three beds.
There are 5*3 = <<5*3=15>>15 beds for those hotel rooms that have three beds in them.
There are 8*2 = <<8*2=16>>16 beds for those hotel rooms that have two beds in them.
There are 15+16 = <<15+16=31>>31 beds in total.
#### 31