Random loading modificering af script

Kan man modificerer dette script til at loade et random billede?
Altså et billede mellem nummer 1 (num) og X angivet antal (max).


num = 1;
max = 10;
function setString(num) {
    i = 'content/random/images/'+num+'.jpg';
}
setString(num);

function preload (){
  preloadBar._alpha = 100;
  imageLoaded = false;
  preloadBar._xscale = loadedBytes = totalBytes = percent = 0;
  this.onEnterFrame = function(){
    totalBytes = ImageHolder.getBytesTotal();
    loadedBytes = ImageHolder.getBytesLoaded();
    percent = Math.floor(loadedBytes/totalBytes*100);
    if(totalBytes > 4) preloadBar._xscale = percent;
    if(!imageLoaded && loadedBytes == totalBytes && totalBytes > 4){
      imageLoaded = true;
      preloadBar._alpha = 0;
    }
  }
}
loadMovie((i), "ImageHolder");
preload()
stop();