JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<?php 
$a =5000;
$b= 225;
$c= 25;
$abc_toal = 5000+225+25; ////Total 5250 set this in hidden input 
?>
<input type="hidden" name="abc_total" id="abc_total" value="5250" />
<p> base fair :  5000</p>
<p> Select Price 
	<select  id="price" >
		<option value="250">250</option>
		<option value="300">300</option>
		<option value="350">350</option>
		<option value="400">400</option>
	</select> 
</p>
<p> tax : 225</p>
<p>other charges : 25</p>

<p id="total_html" >Total price : 5500 </p>
<input type="hidden" id="total" />

JavaScript

$(document).ready(function(){
	$('#price').change(function(){
		var abc_total = parseInt($('#abc_total').val());
		var selected_price = parseInt($(this).val());
		var total = (abc_total+selected_price);
		
		$('#total_html').html('Total price : '+total );
		$('#total').val(total);
		
	});
});