<?php
 
error_reporting(-1);
 
$credit = 40000;// сумма
$percent = 1.03;// процент
$tax = 1000;
$max = 5000;// сколько школьник может платить за месяц
$total = 0;
 
for ($i = 1; $credit > 0; $i ++)
{//начало цикла
 
    if (($credit * $percent + $tax) < $max) 
    {// начало IF
 
        $max = $credit * $percent + $tax;	
 
    }// конец IF
 
  $credit = ($credit * $precent + $tax) - $max;
  $total = $total + $max;
 
  echo "месяц $i, выплачено $total\n";
 
}//конец цикла

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