JSFiddle - React, Tailwind, and code Playground

HTML

<div id='div'></div>
<div id='div1'></div>
<div id='div2'></div>

JavaScript

var test = function () {
    var a = 16.99;
    var b = 21;
    document.getElementById("div").innerHTML = a+b;
};
var test1 = function () {
    var a = 020;
    var b = 2;
    document.getElementById("div1").innerHTML = a*b;
};
var test2 = function () {
    var a = 16.98;
    var b = 21;
    document.getElementById("div2").innerHTML = a+b;
};
test();
test1();
test2();