<?php
 
error_reporting(-1);
 
$credit = 40000; /*сумма кредита*/
$onePatment = 5000; /*может платить а месяц*/
$comission = 1000; /*комиссия в месяц*/
$percent = 1.03; /*процент в месяц*/
$totalPay = 0; /*всего заплатил*/
 
for (i=0,i<15,i++) {
$totalOwe = $credit*$percent +$comission - $onePayment;
   if ($totalOwe >= $onePayment) {
      $totalPay = $totalPay + $onePayment;
   } else {
      $onePayment = $totalOwe;
      $totalPay = $totalPay + $onePayment;
   }
}
echo "Платил $i месяцев\nВсего заплатил $$totalPayment";
 
?>

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