JSFiddle - React, Tailwind, and code Playground

HTML

Price: <input id="price" type="text"/>
<table id="my-table">
<tr>
   <td>Quantity</td>
   <td>Total</td>
</tr>   
<tr>
    <td class="quantity">15,447.84</td>
    <td class="total"></td>
</tr>
<tr>
    <td class="quantity">89.28</td>
    <td class="total"></td>
</tr>
</table>

JavaScript

$(document).ready(function () {
   $('#price').on('change', calTotal);
    
        function calTotal() {
            var p = $('#price').val();
            var q = $('.quantity').text();
           alert(q);
        }
   });