Done

how_old_are_you.rb

@@ -0,0 +1,8 @@
+require_relative './current_age_for_birth_year.rb'
+
+puts "What year were you born?"
+birth_year = gets.to_i
+
+users_age = current_age_for_birth_year(birth_year)
+
+puts "You are: " "+ users_age.to_s + " " years old."

spec/current_age_for_birth_year_spec.rb

@@ -3,7 +3,11 @@
 describe "current_age_for_birth_year method" do
   it "returns the age of a person based on the year of birth" do
     age_of_person = current_age_for_birth_year(1984)
-    
+
     expect(age_of_person).to eq(32)
   end
 end
+
+def current_age_for_birth_year (birth_year)
+  2016 - birth_year
+end

spec/how_old_are_you.rb

@@ -0,0 +1,8 @@
+require_relative './current_age_for_birth_year.rb'
+
+puts "What year were you born?"
+birth_year = gets.to_i
+
+users_age = current_age_for_birth_year(birth_year)
+
+puts "You are: " "+ users_age.to_s + " " years old."