JSFiddle - React, Tailwind, and code Playground

HTML

<label class="price">120</label>
<label class="price">250</label>
<label class="price">342</label>
<label id="total"></label>

JavaScript

jQuery(document).ready(function ($) {
    $('#total').text(function () {
        return $('.price').map(function () {
            return +$(this).text()
        }).get().reduce(function (pv, cv) {
            return pv + cv;
        }, 0);
    });
});