<?php
// define the premium values for males and females
$male_premiums = array(
    18 => 100,
    25 => 200,
    40 => 300,
    60 => 400
);

$female_premiums = array(
    18 => 80,
    25 => 150,
    40 => 250,
    60 => 350
);

// get the user's age and sex from the form
$age = $_POST['age'];
$sex = $_POST['sex'];

// check if the user wants to multiply the premium values
if (isset($_POST['multiply']) && $_POST['multiply'] == 'on') {
    $factor = 2;
} else {
    $factor = 1;
}

// display the premium tables
echo '<h2>Male Premiums:</h2>';
echo '<table>';
echo '<tr><th>Age</th><th>Premium</th></tr>';
foreach ($male_premiums as $a => $p) {
    $p = $p * $factor;
    echo '<tr><td>' . $a . '</td><td>' . $p . '</td></tr>';
}
echo '</table>';

echo '<h2>Female Premiums:</h2>';
echo '<table>';
echo '<tr><th>Age</th><th>Premium</th></tr>';
foreach ($female_premiums as $a => $p) {
    $p = $p * $factor;
    echo '<tr><td>' . $a . '</td><td>' . $p . '</td></tr>';
}
echo '</table>';
?>

<form method="post">
    <label for="age">Age:</label>
    <select id="age" name="age">
        <option value="18">18</option>
        <option value="25">25</option>
        <option value="40">40</option>
        <option value="60">60</option>
    </select>
    <br>
    <label for="sex">Sex:</label>
    <select id="sex" name="sex">
        <option value="male">Male</option>
        <option value="female">Female</option>
    </select>
    <br>
    <label for="multiply">Multiply premium values:</label>
    <input type="checkbox" id="multiply" name="multiply">
    <br>
    <input type="submit" value="Compare premiums">
</form>