diff --git a/tests/Phpml/Math/Statistic/MeanTest.php b/tests/Phpml/Math/Statistic/MeanTest.php
index 2e57ade..f0dca3b 100644
--- a/tests/Phpml/Math/Statistic/MeanTest.php
+++ b/tests/Phpml/Math/Statistic/MeanTest.php
@@ -13,5 +13,6 @@ class MeanTest extends \PHPUnit_Framework_TestCase
         $delta = 0.01;
         $this->assertEquals(3.5, Mean::arithmetic([2, 5]), '', $delta);
         $this->assertEquals(41.16, Mean::arithmetic([43, 21, 25, 42, 57, 59]), '', $delta);
+        $this->assertEquals(1.7, Mean::arithmetic([0.5, 0.5, 1.5, 2.5, 3.5]), '', $delta);
     }
 }