Simple way to calculate stars ratings like ecomerce

avg.php

<?php

// our php array for example, if you using data from database, make it
$array = [
	252, 124, 40, 29, 1
];

// stars, 1 - 5
$star = [
	5, 4, 3, 2, 1	
];

// loop for multiplication stars and user rate
for($i=0; $i<count($array); $i++) {
	$rating[] = $array[$i] * $star[$i];
}

// calculate
$data = array_sum($rating) / array_sum($array);

// get 2 value after coma using php function round
$result = round($data, 2);

// display result
print_r($result);