Nodejs Utililty Methods Array Average

Array.prototype.average = function(arr) {
  if(!arr) arr = this;
  var len =  arr.length, i, avg = 0;
  for( i = 0; i < len; i++ ) {
    avg += arr[i];
  return avg / len;

Array.prototype.average = function (fun) {
    return this.sum(fun) / this.length;
};

Array.prototype.avg = function(){
  return this.sum() / this.length;
};
Array.prototype.sum = function(){
  for (var i = 0, sum = 0 ; i != this.length; ++i) {
    var n = this[i];
    if(!isNaN(n)) {
      sum += n*1;
  return sum;
};

Array.prototype.avg = function() {
  var av, num, _i, _len;
  av = 0;
  for (_i = 0, _len = this.length; _i < _len; _i++) {
    num = this[_i];
    av = av + num;
  return av / this.length;
};
...

Array.prototype.avg = function() {
  var av = 0;
  var cnt = 0;
  var len = this.length;
  for (var i = 0; i < len; i++) {
    var e = +this[i];
    if(!e && this[i] !== 0 && this[i] !== '0') e--;
    if (this[i] == e) {av += e; cnt++;} }
  return av/cnt;
...

Array.prototype.avg = function () {
  var sum=0;
  var drops=this.drops();
  for (var i = 0; i < this.length; i++)
    if (+this[i] !== 0)
      sum += +this[i];
  return (sum/(this.length-drops));

Array.prototype.findAverage = function(){
    var length = this.length;
    var average = 0;
    for(var i = 0; i < length; i++){
        var value = this[i];
        average += value;
    return average / length;
var numbers = [1, 34, 5, 17, 2, 3, 90];
var average = numbers.findAverage();
for(key in numbers) {
    var message = key + ' = ' + numbers[key];
    if(numbers[key] < average){
        message += ' \\/'
    else {
        message += ' /\\'
    console.log(message);

Array.prototype.findAverage = function(){
    var length = this.length;
    var average = 0;
    for(var i = 0; i < length; i++){
        var value = this[i];
        average += value;
    return average / length;
var numbers = [1, 34, 5, 17, 2, 3, 90];
var average = numbers.findAverage();