AS movement issues for dynamic mcs

here is an explanation of what im trying to accomplish:

i have a wire that i want these i guess papers to fly up and attach to. i want one paper to fly up, move over and the next flies up, and the process continues for 10 papers. the last one will not move itll just fly up and stay at its spot, so it ends up looking like a clothesline with clothes on it i guess at the end spread evently out. the problem im having is that right now, with my current code, the papers all fly up at one time, already positioned evenly apart, and then they all go together to one spot on the left side (one on top of the other) and move over 42 pixels, so it looks like they are stacked 42 pixels away from the starting point, instead of evenly moving apart as the animation progresses. here is the code:

// ------------------------ THUMBNAIL CREATION ACTIONS ------------------------
this.createEmptyMovieClip("thumbHolder_mc", this.getNextHighestDepth());
thumbHolder_mc._x = 180;
thumbHolder_mc._y = 748;
function thumbsUp(whichOne):Void {
    thumbTween = new mx.transitions.Tween(whichOne, "_y", mx.transitions.easing.Back.easeIn, 90, 0, 20, false);
    thumbTween.onMotionFinished = function() {
        thumbRight = new mx.transitions.Tween(whichOne, "_x", mx.transitions.easing.Regular.easeIn, 7, 49, 12, false);
    };
}
function distributeThumbs():Void {
    // code
}
var nextX:Number = 7;
for (var i:Number = 0; i < 10; i++) {
    var thumbnail = thumbHolder_mc.attachMovie("thumb", "thumb" + i + "_mc", 1000 + i);
    thumbsUp(thumbnail);
    thumbnail._x = nextX;
    nextX += 42;
    thumbnail.onRollOver = function() {
        this.swapDepths(10000);
    };
}

any help is greatly appreciated, thanks in advance.