diff --git a/math/factorial/ruby/factorial-functional.rb b/math/factorial/ruby/factorial-functional.rb
new file mode 100644
index 0000000000..0871fb5d00
--- /dev/null
+++ b/math/factorial/ruby/factorial-functional.rb
@@ -0,0 +1,7 @@
+def fact(n)
+  (1..n).inject :*
+end
+
+puts "Enter number: "
+n = gets.to_i
+puts "#{n}! = #{fact(n)}"