1. Math Quiz

HI: To all that are good at math try this,you will get it wrong perhaps... 
Note: This riddle must be DONE IN YOUR HEAD and NOT using paper and pen. 
Please do not cheat yourself. 
Take 1000 and add 40 to it. 
Now add another 1000. 
Now add 30. Now add another 1000. 
Now add 20. 
Now add another 1000. 
Now add 10. 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
What is the total? (scroll down for answer) 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
* 
* 
* 
* 
* 
* 
* 
* 
* 
* 
* 
* 
* 
* 
Did you get 5000? 

The correct answer is actually 4100. Don't believe it? Check with your calculator!