PHP random script question

[weisswolfen]

New and happy to be part of this forum to learn and have some php fun.
I'm new at PHP and I have a script to get images placed at random everytime the header is refreshed. My problem is that I don't know how to insert the PHP script in a HTML DIV. Is working as a PHP stand alone and rotating well, but when I get the script in the HTML page doesn't work.
I don't want to change the page from HTML to PHP since I have AJAX and Fjax in the same page and I don't know if they would work in PHP. This is the script:

<div class="lowtitle">

<?php
$images = 5;
$path = "shotrotation/";
$random = rand(1,$images);
echo "<img src=$path"."$random".".gif"." border=\'0\'>"
?>

</div>

Any suggestions how to make it work?
Thanks

[reins]

php only works if the page extension is .php ...