JSFiddle - React, Tailwind, and code Playground

HTML

<div id="send_cart">
    <form method="post" action="">
    <div class="borderline"></div>
    <div id="cart_listing">
	    <table cellspacing="2" cellpadding="0" border="0" width="320">
	        <tr>
	            <td width="170" valign="top" align="left">
	                <div class="product_name">Basic standby overlay</div>
	                </div>
	            </td>
	            <td width="30" valign="top" align="center">
	                <input type="text" class="quantity" value="1" maxlength="2" />
	            </td>
	            <td width="70" valign="top" align="center">
	                <div class="product_total_cost price" data-val="10">10 €</div>
	            </td>
	            <td width="9" valign="top" align="right">
	                <div class="remove_product">X</div>
	            </td>
	        </tr>
	    </table>
        <table cellspacing="2" cellpadding="0" border="0" width="307">
        <tr>
            <td width="190" valign="top" align="left">
                <div class="faster" data-val="10">Discount</div>
            </td>
            <td width="70" valign="top" align="center">
                <div class="discounted" data-val="25">-10 €</div>
            </td>
        </tr>
    </table>
        <table cellspacing="2" cellpadding="0" border="0" width="307">
        <tr>
            <td width="100" valign="top" align="left">
                <div class="faster" data-val="10">Faster delivery</div>
            </td>
            <td width="100" valign="top" align="center">
                <span class="cart_eta">(2b. days) 
                	<?php 
					$date = date('d M');
					$date = strtotime($date);
					$date = strtotime("+2 day", $date);
					echo date('M dS', $date);
					?>
				</span>
            </td>
            <td width="70" valign="top" align="center">
                <div class="product_total_cost faster" data-val="10">10 €</div>
            </td>
        </tr>
    </table>
    <div class="cart_listing_end">
        <table...

JavaScript

$(document).ready(function($){
    $('#cart_listing .quantity').change(function (event) {
        $quan = $(this);
        console.log($quan.parent().next()[0]);
        $quan.parent().next().find('.price').text(function () {
            return $quan.val() * parseInt($(this).attr('data-val'), 10) + ' €';
        });
            var total = 0;
            $('#cart_listing .price').each(function(k, v){
                total += parseFloat($(v).text(), 10); 
            });
            
            $('#cart_listing .faster').text(function () {
                faster = parseInt($(this).attr('data-val'), 10);
                return $(this).attr('data-val' + ' €');
            });

            var discount_pct = parseInt($("#cart_listing .discount").data("val"), 10);
            var discount = -(total * discount_pct/100);

            $('#cart_listing .discounted').text('-' + -discount + ' €');
            $('#cart_listing #total').text(total + discount + faster + ' €')
    });
});