How do you dynamically move duplicated _mc's?

Question

Hi there,
my first forum question, i.e. should be easy for most. Yay!
I am trying to make every duplicated _mc in the following
code move right 5 pix from each other. With this code, it seems
only one duplicated _mc moved 5 pix. Furthermore, my
trace(["rond_mc"+i]._x) returns 10 "undefined"s? What am I doing
wrong?
Many thanks for your consideration and help,
// Code ============
var t:Number = 0;
_root.attachMovie("rond_mc", "rond_mc",
this.getNextHighestDepth);
trace("rond_mc._x = " + rond_mc._x)
for (var i:Number = 0; i<=10; i++) {
rond_mc.duplicateMovieClip("rond" + i + "_mc", 100+t);
_root["rond" + i + "_mc"]._x += 5;
trace(["rond" + i + "_mc"]._x)
}

Answer 1

use "this" in trace
trace(this["rond" + i + "_mc"]._x);