diff --git a/spec/15b_binary_search_spec.rb b/spec/15b_binary_search_spec.rb
index 7746691..6b84f89 100644
--- a/spec/15b_binary_search_spec.rb
+++ b/spec/15b_binary_search_spec.rb
@@ -100,7 +100,7 @@
       subject(:mid_game) { described_class.new(0, 9, mid_number, 4) }
 
       it 'is not game over' do
-        expect(mid_game).to_not be_game_over
+        expect(mid_game).not_to be_game_over
       end
     end
   end
diff --git a/spec_answers/10_drink_answer_spec.rb b/spec_answers/10_drink_answer_spec.rb
index b800b09..954412e 100644
--- a/spec_answers/10_drink_answer_spec.rb
+++ b/spec_answers/10_drink_answer_spec.rb
@@ -36,7 +36,7 @@
       subject(:juice_drink) { described_class.new('juice', 8) }
 
       it 'is not full' do
-        expect(juice_drink).to_not be_full
+        expect(juice_drink).not_to be_full
       end
     end
   end
diff --git a/spec_answers/11b_cat_answer_spec.rb b/spec_answers/11b_cat_answer_spec.rb
index 477b8ac..41bdb21 100644
--- a/spec_answers/11b_cat_answer_spec.rb
+++ b/spec_answers/11b_cat_answer_spec.rb
@@ -34,7 +34,7 @@
   end
 
   it 'is not hungry' do
-    expect(lucy).to_not be_hungry
+    expect(lucy).not_to be_hungry
   end
 
   it 'is hiding' do
diff --git a/spec_answers/11c_dog_answer_spec.rb b/spec_answers/11c_dog_answer_spec.rb
index 2b05e28..3ec2ef4 100644
--- a/spec_answers/11c_dog_answer_spec.rb
+++ b/spec_answers/11c_dog_answer_spec.rb
@@ -32,7 +32,7 @@
   end
 
   it 'is not barking' do
-    expect(ollie).to_not be_barking
+    expect(ollie).not_to be_barking
   end
 
   it 'is sleeping' do
diff --git a/spec_answers/13_input_output_answer_spec.rb b/spec_answers/13_input_output_answer_spec.rb
index c0bf303..c47fc93 100644
--- a/spec_answers/13_input_output_answer_spec.rb
+++ b/spec_answers/13_input_output_answer_spec.rb
@@ -83,7 +83,7 @@
       subject(:game_mid) { described_class.new(5, '2') }
 
       it 'is not game over' do
-        expect(game_mid).to_not be_game_over
+        expect(game_mid).not_to be_game_over
       end
     end
   end
diff --git a/spec_answers/14_find_number_answer_spec.rb b/spec_answers/14_find_number_answer_spec.rb
index 1de6d0e..fb4bff1 100644
--- a/spec_answers/14_find_number_answer_spec.rb
+++ b/spec_answers/14_find_number_answer_spec.rb
@@ -150,7 +150,7 @@ def update_range
       subject(:game_mid) { described_class.new(0, 9, number_mid, 4) }
 
       it 'is not game over' do
-        expect(game_mid).to_not be_game_over
+        expect(game_mid).not_to be_game_over
       end
     end
   end