title: Ruby Hash - sort by value and print keys
body: <p>This is my hash.</p>
  
  <pre><code>=&gt; {"f11"=&gt;1, "f12"=&gt;3, "f13"=&gt;3, "f07"=&gt;5, "f10"=&gt;1}
  </code></pre>
  
  <p>I'd like to sort by the values largest to smallest and then make an array out of the keys.</p>
  
  <pre><code>=&gt; ["f07", "f12", "f13", "f11", "f10"]
  </code></pre>