Stuck at query. I want total number of students in each board
<p>I have two tables student and grade.<br>
They are linked by PK FK relation from Student (count) to Grades (marksID).
I have to select percentage of student who has scored more than 70 percent marks, Board wise.<br>
Every city has its own board.<br>
The query is:</p>

<pre><code>select g3.board,(count(g2.percentag)/ count(board))*100
from  loadbise.grade as g2, loadbise.student as g3
where g2.marksID=g3.countt
and percentag &gt; 70
group by g3.board;
</code></pre>

<p>I know the value for count(ge.percentag) and count(board) is same.<br>
I am stuck at this count(board) point.<br>
I want total Number of students in each board in count(board).<br>
What am I missing???<br>
The Schema is..<br>
<a href="https://i.stack.imgur.com/rurIn.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/rurIn.png" alt="enter image description here"></a></p>