JSFiddle - React, Tailwind, and code Playground

HTML

<table>
    <tr>
        <td class="one"><input type="text"></td><td class="two"><input type="text" value="12.00"></td><td class="three"><input type="text"></td>
    </tr>
    <tr>
        <td class="one"><input type="text"></td><td class="two"><input type="text" value="22.13"></td><td class="three"><input type="text"></td>
    </tr>
    <tr>
        <td class="one"><input type="text"></td><td class="two"><input type="text" value="14.1"></td><td class="three"><input type="text"></td>
    </tr>
</table>

JavaScript

$(".one input, .two input").change(function() { 
    var $row = $(this).closest("tr");
    var $one = $(".one input", $row);
    var $two = $(".two input", $row);

    var val1 = $one.val();
    var val2 = $two.val();
    var val3 = val1 * val2;

    $(".three input", $row).val(val3);
});