title: issue in jquery radio button selection
body: <p>I am not much more flexible with jquery. I have some li tags and for each li tag, I have one input tag of type radio like:</p>
  
  <pre><code>&lt;li&gt;&lt;input type='radio' value='cool' name='radiooption' id='2'&gt;2&lt;/li&gt;
  &lt;li class='answered'&gt;&lt;input type='radio' name='radiooption' value='cool1' id='3'&gt;3&lt;/li&gt;
  &lt;li&gt;&lt;input type='radio' value='cool' name='radiooption' id='4'&gt;4&lt;/li&gt;
  &lt;li&gt;&lt;input type='radio' value='cool' name='radiooption' id='5'&gt;5&lt;/li&gt;
  </code></pre>
  
  <p>Now by jquery how to add <code>checked="checked"</code> for radio button which is under <code>li</code> tag having <code>class='answered'</code>?</p>
  
  <p>Please guide me.</p>