title: SQL statement using count and avg
body: <p>My question -> what's the average of children a woman can have. Give the number of children in the column. </p>
  
  <pre><code>Relations:
  
  human (name, gender, age) 
  parent (ParentName, ChildName) -&gt; is subset of human(name)
  </code></pre>
  
  <p>What I got so far:</p>
  
  <pre><code>SELECT AMOUNT
  FROM human h
  JOIN parent p ON h.name = p.parentname
  WHERE gender = 'f' AND h.name IN (p.parentname) AND AVG(COUNT(childname))
  </code></pre>
  
  <p>Desired outcome:</p>
  
  <pre><code>AMOUNT : 1.33333333333333333333333333333333333333E00
  </code></pre>