title: Number of hours between two dates - Ruby
body: <p>Say I want the difference between tomorrow and now (in hours).</p>
  
  <p>What I've tried:</p>
  
  <pre><code>t = (DateTime.tomorrow - DateTime.now)
  (t / 3600).to_i
  =&gt; 0
  </code></pre>
  
  <p>Why does it give 0?</p>
  
  <p>What am I doing wrong?</p>