title: SQL - list of student ids and average mark in 2 decimal places
body: <p>Question: Write a query to display list of student ids and average mark in 2 decimal places if their average mark is greater than 80. Give an alias to average mark as avg_mark. Sort the result based on average mark.</p>
  <p><a href="https://i.stack.imgur.com/F6SOS.png" rel="nofollow noreferrer">Schema for reference</a></p>
  <p>I wrote this query, but the result doesn't match the expected output.</p>
  <pre><code>select student_id, round(avg(value)) as avg_mark 
  from mark
  where value&gt;80    -------well this is wrong as I need to compare with an average of value
  group by student_id
  order by avg_mark
  </code></pre>
  <p>Running this query gives wrong output [linked below]</p>
  <p><a href="https://i.stack.imgur.com/OEiVL.png" rel="nofollow noreferrer">Output</a></p>
  <p>Thank you!!!</p>