getNewSize

var pct:Number = getNewSizeMax(content.width, content.height, mask_mc.width * 1.1, mask_mc.height * 1.1);
content.scaleX *= pct;
content.scaleY *= pct;
 
private function getNewSizeMax(initW:Number, initH:Number, endW:Number, endH:Number):Number
{
	var pct:Number = 1;
	var pct2:Number = 1
	var retorno:Number;
	if (initW != endW)
		pct = extartPercent(initW, endW);
	if (initH != endW)
		pct2 = extartPercent(initH, endH);
	if(pct > pct2)
		retorno = pct;
	else
		retorno = pct2;
	return retorno;
}
 
private function extartPercent(n1:uint, n2:uint):Number
{
	return n2 / n1;
}