diff --git a/app/helpers/exercises_helper.rb b/app/helpers/exercises_helper.rb
index 280f571a4..be71aedab 100644
--- a/app/helpers/exercises_helper.rb
+++ b/app/helpers/exercises_helper.rb
@@ -234,7 +234,7 @@ module ExercisesHelper
           shixun_score_array.each_with_index do |s,index|
             right_answer = (index == 0)
             if effictive_users_count == 0
-              score_percent = "0.0"
+              score_percent = 0.0
             else
               score_percent = (s.to_i / effictive_users_count.to_f ).round(3)
             end