Here you can find the source of toPercentage(radix)
Number.prototype.toPercentage = function (radix) { var num = this * 100; return num.roundToFixed(radix); };
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) + '%'; };