diff --git a/lib/rubocop/cop/mixin/preceding_following_alignment.rb b/lib/rubocop/cop/mixin/preceding_following_alignment.rb
index 1c66a94b580..da47e08fecd 100644
--- a/lib/rubocop/cop/mixin/preceding_following_alignment.rb
+++ b/lib/rubocop/cop/mixin/preceding_following_alignment.rb
@@ -93,13 +93,15 @@ def aligned_char?(range, line)
       end
 
       def aligned_assignment?(range, line)
-        range.source[-1] == '=' && line[range.last_column - 1] == '=' ||
+        (range.source[-1] == '=' && line[range.last_column - 1] == '=') ||
           aligned_with_append_operator?(range, line)
       end
 
       def aligned_with_append_operator?(range, line)
-        range.source == '<<' && line[range.last_column - 1] == '=' ||
-          range.source[-1] == '=' && line[(range.last_column - 2)..(range.last_column - 1)] == '<<'
+        last_column = range.last_column
+
+        (range.source == '<<' && line[last_column - 1] == '=') ||
+          (range.source[-1] == '=' && line[(last_column - 2)..(last_column - 1)] == '<<')
       end
 
       def aligned_identical?(range, line)