title: How do I change the total price when the quantity changes?
body: <p>When the user enters the number of tickets they want in the text box, the subtotal should automatically change/update. What do I have to add to get this working?</p>
  
  <pre><code>&lt;form id="confirmInfo" action="bookingsuccess.html"&gt;
    &lt;p&gt;Number of tickets :
      &lt;input type="text" type="num" /&gt;
    &lt;/p&gt;
    &lt;p&gt;Price Per ticket : $7&lt;/p&gt;
    &lt;p&gt;Booking fee : $2&lt;/p&gt;
    &lt;p&gt;Subtotal : &lt;b&gt;$&lt;span id="total"&gt;0&lt;/span&gt;&lt;/b&gt;
    &lt;/p&gt;
    &lt;form name="myform" action="bookingsuccess.php" method="post"&gt;
      &lt;button&gt;Book&lt;/button&gt;
    &lt;/form&gt;
    &lt;button&gt;Cancel&lt;/button&gt;
  &lt;/form&gt;
  </code></pre>