YA: Simple Phone Number Checking Mod3

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml…
<html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title>Phone numbers</title>
        <meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
    </head>
<body>
    <?php
        function validPhoneNum($i){ // Returns true if valid phone number, false if not
            $numNums = strlen(preg_replace('/[^0-9]/', '', $i));
            return (!($numNums !== 7 && $numNums !== 10) && !preg_match("/[^0-9\(\)\-\s\.]+/",$i));
        }
        $phoneNumbers = array("111-1111","(111) 111-1111","111-111-1111","111111",    "111.555.1234","","aaa-aaaa");

        // Table is merely to show functionality of function validPhoneNum();
        echo '<table cellspacing="1" border="1">
            <tr>
                <th>Number</th>
                <th>Valid</th>
            </tr>';
        foreach ($phoneNumbers as $phone) {
            $valid = validPhoneNum($phone);
            echo '<tr>
                <td>' . $phone . '</td>
                <td style="background-color: #' . (($valid)? '090' : '900') . ';">' . (($valid)? '' : 'NOT ') . 'Valid</td>
            </tr>';
        }
        echo '</table>';
    ?>
</body>
</html>