avg.php

<?php
function avg(){
    return array_sum(func_get_args()) / func_num_args();
}

function avgr($a){
    return array_sum($a) / count($a);
}


function avg() {
    $sum = 0;
    $num = func_num_args();
    for($i = 0; $i < $num; $i++) {
        $sum += func_get_arg($i);
    }
    $avg = $sum / $num;
    return $avg;
}

function avgr($a) {
    $sum = 0;
    $num = count($a);
    for($i = 0; $i < $num; $i++) {
        $sum += $a[$i];
    }
    $avg = $sum / $num;
    return $avg;
}

printf("%.2f\n", avg(2,1,2,1,3,4,5,1,3,6));
printf("%.2f\n", avgr(array(2,1,2,1,3,4,5,1,3,6)));