diff --git a/BasicProgramming/Program.cs b/BasicProgramming/Program.cs
index f63e19c..dd0c1d2 100644
--- a/BasicProgramming/Program.cs
+++ b/BasicProgramming/Program.cs
@@ -316,7 +316,7 @@ namespace BasicProgramming
             var sum = 0;
             for (int i = a; i <= b; i++)
             {
-                sum++;
+                sum = sum + i;
             }
 
             double average = (double)sum / (b - a + 1);