JSFiddle - React, Tailwind, and code Playground

HTML

<div></div>

JavaScript

var _cf = (function() {
  function _shift(x) {
    var parts = x.toString().split('.');
    return (parts.length < 2) ? 1 : Math.pow(10, parts[1].length);
  }
  return function() { 
    return Array.prototype.reduce.call(arguments, function (prev, next) { return prev === undefined || next === undefined ? undefined : Math.max(prev, _shift (next)); }, -Infinity);
  };
})();

Math.a = function () {
  var f = _cf.apply(null, arguments); if(f === undefined) return undefined;
  function cb(x, y, i, o) { return x + f * y; }
  return Array.prototype.reduce.call(arguments, cb, 0) / f;
};

$("div").append("test 1 + 1 = "+Math.a(1,1));
$("div").append("<br/>test 76.65 + 38.45 = "+Math.a(76.65, 38.45));