title: jQuery, javascript - How add decimal numbers?
body: <p>I have created function after button click:</p>
  
  <pre><code>var cena_poczatkowa = parseFloat($("#cena_aktualna").text());
      var cena_dodana = cena_poczatkowa + 1.01;
      $("span#cena_aktualna").text(cena_dodana);
  </code></pre>
  
  <p>And span in html:</p>
  
  <pre><code>&lt;span id="cena_aktualna"&gt;0.00&lt;/span&gt;
  </code></pre>
  
  <p>Everything working fine, after every click number is changed in span: 1.01, 1.02.
  But after thrid click I see 3.0300000000000002.
  After fourth click I see again properly 4.04.
  Why after third click I see this strange number?</p>
  
  <p>Here is my working script so you can see this bug: <a href="http://jsfiddle.net/H3pfH/" rel="nofollow">http://jsfiddle.net/H3pfH/</a></p>