Nodejs Utililty Methods Number to Percentage Format

Number.prototype.toPercent = function(n) {
  n = n || 0;
  return (Math.round(this * Math.pow(10, n + 2)) / Math.pow(10, n)).toFixed(n) + '%';

Number.prototype.toPercent = function (ofTotalAmount) {
    "use strict";
    var n, t;
    var sign, suffix, i;
    n = this;
    try {
        t = (typeof ofTotalAmount === 'undefined' || isNaN(ofTotalAmount)) ? 100 : ofTotalAmount;
        if (t === 0) throw "division exception averted";
        if (t <= n) throw "is too low";
...

Number.prototype.toPercent = function(places) {
  return (this * 100).toFixed(places) + '%';
};

Number.prototype.toPercentage = function (radix) {
    var num = this * 100;
    return num.roundToFixed(radix);
};