Sequential x, duplicate movie, AS

Okay, lets say i have this:


numB = 5
for(i=1; i<numB; i++){
	box.duplicateMovieClip("box" add i, i+100);
}

	

how would i set the _x of each box, to be 100 greater then the previous box _x
with as?

so they would appear in a line like # # # # # ?