JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js"></script>
<div id="a">0</div>
<div class="b">
Soru 1
<input type="radio" value="5" name="x">
<input type="radio" value="10" name="x">
<input type="radio" value="15" name="x">
<input type="radio" value="20" name="x">
</div>
<div class="b">
Soru 2
<input type="radio" value="5" name="y">
<input type="radio" value="10" name="y">
<input type="radio" value="15" name="y">
<input type="radio" value="20" name="y">
</div>

JavaScript

$(function() {

  $(document).on('change', '.b input[type="radio"]', function() {
    var rx = $('input[name="x"]:checked');
    var ry = $('input[name="y"]:checked');
    
  	var rxVal = rx.val() ? rx.val() : 0;
    var ryVal = ry.val() ? ry.val() : 0;
    
    var total = Number(rxVal) + Number(ryVal);
    
  	$('#a').html(total);
  })
  
});