title: How to remove a class that starts with...?
body: <p><strong>HTML</strong></p>
  
  <pre><code>&lt;div class="ativo37 and many other classes"&gt;&lt;/div&gt;
  &lt;div class="another classes here with ativo1"&gt;&lt;/div&gt;
  &lt;div class="here ativo9 and more two or three"&gt;&lt;/div&gt;
  </code></pre>
  
  <p><strong>JS</strong></p>
  
  <pre><code>$("div[class^='ativo']").on("click", function(){
      $(this).removeClass("^='ativo'"); // How to achieve it?
  });
  </code></pre>
  
  <p>What can I do instead of <code>.removeClass("^='ativo'");</code>?</p>
  
  <p><a href="http://jsfiddle.net/vq19cnrq/" rel="noreferrer">JSFiddle</a></p>