diff --git a/2020/ruby/day_10.rb b/2020/ruby/day_10.rb
index ad67898..51f8c71 100644
--- a/2020/ruby/day_10.rb
+++ b/2020/ruby/day_10.rb
@@ -26,4 +26,4 @@ p dist
   .slice_when {|a,b| a != b }
   .select {|run| run.first == 1 }
   .map {|run| arrangements[run.size] }
-  .inject {|a,b| a*b }
+  .inject(&:*)