title: progress increase value not working well with percent
body: <p><a href="http://jsfiddle.net/2gsNy/1/" rel="nofollow">http://jsfiddle.net/2gsNy/1/</a></p>
  
  <p>I want make it +10, work for the 1st but the second and after it increase way than 10.. </p>
  
  <p>my js</p>
  
  <pre><code>$('#test').on('click', function (e) {
      $this = $('#progressbarr &gt; div').width();
      var i = $this + 10;
      $('#progressbarr &gt; div').css('width', (i + '%'));
  
      $progress_bar = $('#progressbarr');
      var progressbar_width = Math.floor(100 * ($progress_bar.find('div').width()) / $progress_bar.width());
      $progress_bar.find('span').text(progressbar_width + '%');
  
  });
  </code></pre>