Really simple answer I am sure

Hey guys i have a preloader and some dynamic text outputting the %, but its in decimal form. How do I make it a whole number.

here is my as:
[AS]
stop();
this.onEnterFrame = function() {
var amount:Number = this.getBytesLoaded() / this.getBytesTotal() * 100;
loader._xscale = amount;
percent_txt.text = “%” + amount;
if(amount == 100) {
this.gotoAndPlay(3);
delete this.onEnterFrame;
}
}
[/AS]

I am assuming its going to be something to do with Math.round, but I dont know where to put it. Thanks guys.
-Ronnie