sorting array is not working

[merbin2012]

The following sort() method not working please solve this

<?php 
 $numbers = array(30, 71, 5, 29, 17); 
 sort($numbers); 

 $arrlength = count($numbers); 
 for($x = 0; $x < $arrlength; $x++) { 
  echo $numbers[$x]; 
  echo "<br>"; 
 }

?>