JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.2/themes/ui-lightness/jquery-ui.css">
<em>start</em>
<em>start</em>
<em>start</em>
<em>start</em>
<em>start</em>

JavaScript

var $ems = $('em');

setInterval(function() {
    $ems.each(function() {
        var random = ~~(Math.random() * 10);
        $(this).text(random);
    });
},500);