test1

HTML

<div id="red">
    <div id="box_green" class="green"></div>  
</div>

CSS

div#red {
	width:500px;
    height:200px;
	position:relative; 
	alignment:center;
    border:solid 1px black;
    background-color:#F88;
}
div.green{
	width:100px;
	height:50px;
    border:1px solid black;
    background-color:#0f0;
    cursor:pointer;
    position:absolute;
}

JavaScript

$(document).ready(function(){
       	$('.green').draggable({opacity:'1', helper:'clone'});	  
        $('#red').droppable({drop:dropped});
});
function dropped(ev, info) {  
	var relX = ev.clientX;
	var relY = ev.clientY;
    $(info.draggable)
		  .clone()
		  .css({
			   "left": relX-50, 
				"top" : relY-25
			   })
		  .prependTo('#red');
}