JSFiddle - React, Tailwind, and code Playground

HTML

<label>Width</label><input type="text" id="width" />
<br>
<label>Length</label><input type="text" id="length" />
<br>
<label>Total</label><input type="text" id="total"/>

JavaScript

var w = $('#width').val();
var l = $('#length').val();
var total1 = 2;
var total2 = 3;

if((w * l) > 5){
    total = total1 * (w + l);
    parseInt($('#total').val('total'));
}
if((w * l) < 5){
    totalnew = total2 * (w + l);
    parseInt($('#total').val(totalnew));
}