title: Operation not working when using number properties (returns NaN)
body: <p>What's the problem in using number properties? I'm trying to do a simple calculation involving numbers and it returns NaN.</p>
  
  <pre><code>function test () {
      var that = this;
  
      this.usersCount = 2;
      this.totalSeeds = 10;
  
      this.test2 = function () {
          console.log(2/10*100); // 20
          console.log(that.usersCount * that.totalSeeds); // 20
          var percentUsersCount = that.usersCount / that.totalseeds * 100; // also tried parseInt() and Number()
          console.log(percentUsersCount); // NaN -- WHY !?!
      }
  }
  
  var test = new test();
  
  test.test2();
  
  var test1 = 2;
  var test2 = 10;
  var percent = test1 / test2 * 100;
  console.log(percent); // 20
  </code></pre>
  
  <p>Why is <code>percentUsersCount</code> NaN?</p>
  
  <p><a href="http://jsfiddle.net/ht2rv1ea/" rel="nofollow">http://jsfiddle.net/ht2rv1ea/</a></p>
  
  <p>Edit: <a href="https://www.youtube.com/watch?v=yI6VXlNRrI0" rel="nofollow">https://www.youtube.com/watch?v=yI6VXlNRrI0</a></p>