<?php
$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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