JSFiddle - React, Tailwind, and code Playground

by Marco

HTML

<span id='thisid' data-discount_tendered='0.00'></span>
<span id='value'>1.10</span>
<button id='btn'>Go</button>

JavaScript

$("#btn").click( function() {
		var discount = parseFloat($("#thisid").attr("data-discount_tendered"));
		var value = parseFloat($("#value").text());
		var newDiscountVal = (discount += value).toFixed(2);;
		$("#thisid").attr("data-discount_tendered", newDiscountVal);
        alert(newDiscountVal)
	});