diff --git a/actionpack/lib/abstract_controller/rendering.rb b/actionpack/lib/abstract_controller/rendering.rb
index 3619ef5cf5..ddc93464cd 100644
--- a/actionpack/lib/abstract_controller/rendering.rb
+++ b/actionpack/lib/abstract_controller/rendering.rb
@@ -121,7 +121,7 @@ module AbstractController
       variables  = instance_variables
       variables -= protected_instance_variables
       variables -= DEFAULT_PROTECTED_INSTANCE_VARIABLES
-      variables.each { |name| hash[name.to_s[1, name.length]] = instance_variable_get(name) }
+      variables.each { |name| hash[name[1..-1]] = instance_variable_get(name) }
       hash
     end
 
diff --git a/activesupport/lib/active_support/core_ext/object/instance_variables.rb b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
index 66caf9bec8..91fdf93eb2 100644
--- a/activesupport/lib/active_support/core_ext/object/instance_variables.rb
+++ b/activesupport/lib/active_support/core_ext/object/instance_variables.rb
@@ -10,7 +10,7 @@ class Object
   #
   #   C.new(0, 1).instance_values # => {"x" => 0, "y" => 1}
   def instance_values #:nodoc:
-    Hash[instance_variables.map { |name| [name.to_s[1..-1], instance_variable_get(name)] }]
+    Hash[instance_variables.map { |name| [name[1..-1], instance_variable_get(name)] }]
   end
 
   # Returns an array of instance variable names including "@". They are strings
diff --git a/activesupport/lib/active_support/string_inquirer.rb b/activesupport/lib/active_support/string_inquirer.rb
index e6b1f39225..f3f3909a90 100644
--- a/activesupport/lib/active_support/string_inquirer.rb
+++ b/activesupport/lib/active_support/string_inquirer.rb
@@ -11,8 +11,8 @@ module ActiveSupport
   #
   class StringInquirer < String
     def method_missing(method_name, *arguments)
-      if method_name.to_s[-1,1] == "?"
-        self == method_name.to_s[0..-2]
+      if method_name[-1, 1] == "?"
+        self == method_name[0..-2]
       else
         super
       end