My solution

Gemfile

@@ -4,3 +4,4 @@ gem 'activerecord'
 gem 'awesome_print'
 gem 'sqlite3'
 gem 'table_print'
+gem 'json', github: 'flori/json', branch: 'v1.8'

Gemfile.lock

@@ -1,3 +1,10 @@
+GIT
+  remote: git://github.com/flori/json.git
+  revision: 7f4cfd853f2c919d854fb95548a19980feff17e8
+  branch: v1.8
+  specs:
+    json (1.8.6)
+
 GEM
   remote: https://rubygems.org/
   specs:
@@ -18,7 +25,6 @@ GEM
     awesome_print (1.2.0)
     builder (3.2.2)
     i18n (0.6.11)
-    json (1.8.1)
     minitest (5.4.2)
     sqlite3 (1.3.10)
     table_print (1.5.3)
@@ -32,5 +38,9 @@ PLATFORMS
 DEPENDENCIES
   activerecord
   awesome_print
+  json!
   sqlite3
   table_print
+
+BUNDLED WITH
+   1.15.0

associations.rb

@@ -15,24 +15,38 @@ def generate_migrations
   ActiveRecord::Migration.create_table :hotels do |t|
     #insert our columns here
 
+    t.string :name
+    t.integer :room_count
+
     t.timestamps null: false
   end
 
   ActiveRecord::Migration.create_table :rooms do |t|
     #insert our columns here
 
+    t.belongs_to :hotel, index: true
+
+    t.integer :rate
+    t.string :location
+
     t.timestamps null: false
   end
 
   ActiveRecord::Migration.create_table :bookings do |t|
     #insert our columns here
 
+    t.belongs_to :user, index: true
+    t.belongs_to :room, index: true
+    t.datetime :check_in
+
     t.timestamps null: false
   end
 
   ActiveRecord::Migration.create_table :users do |t|
     #insert our columns here
 
+    t.string :name
+
     t.timestamps null: false
   end
 end
@@ -47,25 +61,46 @@ def generate_migrations
 
 class Hotel < ActiveRecord::Base
   #insert our associations here
-
+
+  has_many :rooms
+  has_many :bookings, through: :rooms
+
   def to_s
     "#{name} with #{rooms.count} rooms"
   end
+
+  def booked_guests
+     guests = Array.new
+     self.bookings.each do |booking|
+         guests << booking.guest
+     end
+  end
+
 end
 
 class Booking < ActiveRecord::Base
   #insert our associations here
-
+  belongs_to :guest, class_name: "User", foreign_key: "user_id"
+  belongs_to :room
 end
 
 class Room < ActiveRecord::Base
   #insert our associations here
-
+  has_many :bookings
+  belongs_to :hotel
 end
 
 class User < ActiveRecord::Base
   #insert our associations here
-
+  has_many :bookings
+
+  def booked_rooms
+    rooms = Array.new
+    self.bookings.each do |booking|
+      rooms << booking.room
+    end
+    rooms
+  end
 end
 
 #DO NOT CHANGE ANYTHING BELOW THIS LINE.
@@ -74,11 +109,11 @@ def random_loc; (('a'..'e').to_a.sample) + rand(1..5).to_s; end
 
 hotel = Hotel.create!(name: "Westin", room_count: 5)
 
-5.times do 
+5.times do
   hotel.rooms << Room.create!(
     rate: [125,200,175].sample,
     location: random_loc
-  ) 
+  )
 end
 
 user = User.create!(name: "John Smith")