title: Issue with the Nested Queries
body: <p>Hey guys I have been working on this but I am not able solve it. Can any one help me with this please? I tried many ways but couldn't solve it, can anyone help me by using nested queries and just using (GROUP BY, HAVING, SELECT,FROM and WHERE)</p>
  
  <blockquote>
    <p>(Qs)You would like to know the departments with more than 5 full-time
    young employees (Age &lt;25) each department has. Calculate the average
    salary of the employees who work for those departments. This newly
    calculated field should be named as "AvgSalary" and be returned by
    your query.</p>
  </blockquote>
  
  <p>Here is the SCHEMA of this.</p>
  
  <pre><code>Employee(EmployeeID: Integer, EmpName: String, Age: Integer, Salary: Real)  
  Department(DeptID: Integer, DeptName: String, Budget: Real, ManagerID: Integer)
  Works(EmployeeID: Integer, DeptID: Integer, Percent_Time: Integer)
  </code></pre>