title: Ruby float precision
body: <p>As I understand it, Ruby (1.9.2) floats have a precision of 15 decimal digits. Therefore, I would expect rounding float <em>x</em> to 15 decimal places would equal <em>x</em>. For this calculation this isn't the case.</p>
  
  <pre><code>x = (0.33 * 10)
  x == x.round(15) # =&gt; false
  </code></pre>
  
  <p>Incidentally, rounding to 16 places returns true.</p>
  
  <p>Can you please explain this to me?</p>