JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" id="u"> / <input type="text" id="d"> <hr>
<button>Is Divisible?</button>&nbsp;-&nbsp;<span id="a"></span>

JavaScript

function isDivisible(u, d) {
    var numD = Math.max(u.toString().replace(/^\d+\./, '').length, d.toString().replace(/^\d+\./, '').length);
    u = Math.round(u * Math.pow(10, numD));
    d = Math.round(d * Math.pow(10, numD));
    console.log(u + '/' + d);
    return (u % d) === 0;
}

$('button').click(function() {
    $('#a').text(isDivisible(parseFloat($('#u').val()), parseFloat($('#d').val())));
});