ขอถามเกี่ยวกับการเขียนโปรแกรมคำนวนทางคณิตศาสตร์หน่อยครับ คิดไม่ออกจริงๆ

function calculate($number) {
        $bases = [
            ['weight' => 3.6 ,'num' => 5000],
            ['weight' => 1.9 ,'num' => 3000]
        ];

        $type = 1;
        $base_match = 0;
        foreach($bases as $k => $base) {
             if(checkMatch($number, $base['num'])) {
                 $type = 0;
                 $base_match = $k;
             }
        }
        display($number, $bases, $type, $base_match);

    }

    function display($number, $bases, $type, $base_match) {
        $remain = $number;
        $result = [];
        if($type) {
            foreach ($bases as $k => $base) {
                if($remain % $base['num'] == 0) {
                    while($remain >= $base['num'] && ($remain % $base['num'] == 0)) {
                        $result[$k] = floor($remain / $base['num']);
                        $remain = $remain % $base['num'];

                        echo  'weight '.$bases[$k]['weight'].' is ' .$result[$k].' remain = '.$remain."<br>";

                    }
                } else {
                    while($remain >= $base['num']) {

                        $result[$k] = floor($remain / $base['num']);
                        $remain = $remain % $base['num'];

                        echo  'weight '.$bases[$k]['weight'].' is ' .$result[$k].' remain = '.$remain."<br>";
                    }
                }
            }
        } else {
            $result = $number / $bases[$base_match]['num'];
            $remain = 0;
            echo  'weight '.$bases[$base_match]['weight'].' is ' .$result.' remain = '.$remain."<br>";
        }

    }

    function checkMatch($number, $base)
    {
        return $number % $base == 0;
    }

calculate(9000);