หาค่าเฉลี่ย โดยจะใช้ php ดึงค่าเฉลี่ยออกมาโชว์ ต้องใช้คำสั่่งอะไรครับ

<?php
$arr = array(2, 10, 3, 10, 20, 12, 40);
echo Average($arr);

function Average($arr) {
	$array_size = count($arr);

	$total = 0;
	for ($i = 0; $i < $array_size; $i++) {
		$total += $arr[$i];
	}

	$average = (float)($total / $array_size);
	return $average;
}
?>

<?
include "connect.php";
$sql="select  AVG(Settlement) as Avarage
from x 
where Date ='1/4/2005'";
$sqlquery=mysql_db_query($dbname,$SQL);
$num_rows=mysql_num_rows($sqlquery);
while ($table=mysql_fetch_array($num_rows))
{
$SUM=0;
$SUM=$SUM+$table["settlement"];
}
$average=$SUM/$num_rows;
echo $average; 
mysql_close();
?>

<?php
include "connect.php";
$sql="select AVG(settlement) as Average
from x 
where Date ='1/4/2005'";
$sqlquery=mysql_query($sql);
$table=mysql_fetch_array($sqlquery);
$average=$table['Average'];
echo $average;
mysql_close();
?>

<?php
include "connect.php";
$sql="select AVG(settlement) as Average
from x 
where Date ='1/4/2005' UserID = '400183'";
$sqlquery=mysql_query($sql);
$table=mysql_fetch_array($sqlquery);

$average = $table['eva1'] + $table['eva2'] + $table['eva3'] + $table['eva4'] + $table['eva5'] + $table['eva6'] + $table['eva7'] $table['eva8'] + $table['eva9'];

$average2 = $average / $table['scor'];

echo $average2;

mysql_close();
?>