Javascript float addition
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/588004/is-javascripts-math-broken">Is JavaScript&#39;s Math broken?</a>  </p>
</blockquote>



<pre><code>&lt;html&gt;
&lt;body&gt;

&lt;script type="text/javascript"&gt;
 var w = 0;
 var weight1 = parseFloat("0.6");
 var weight2 = parseFloat("0.3");
 w = weight1 + weight2;

 document.write("total weight: " + w);
&lt;/script&gt;

&lt;/body&gt;
&lt;/html&gt;
</code></pre>

<p>Why does this print 0.8999999999999999  and not 0.90000000</p>
