$(document).ready(function() {
 
 $("select").sb({ ddCtx: function() { return $(this).closest("form"); } });
 
 $('#paper').change(function(){
										 
		  var product = $('#paper').val();
		  var size = $('#size').val();
		  var quantity = $('#quantity').val();
		  var dataString = "product=" + product + "&size=" + size + "&quantity=" + quantity;
		  
		   $.ajax({
			type: "POST",
			url: "qdata.php",
			data: dataString,
			cache: false,
			success:function(html){
			
			$("#cost").val(html);	
			}
										 
		 });
			
		});
 
  $('#size').change(function(){
										 
		  var product = $('#paper').val();
		  var size = $('#size').val();
		  var quantity = $('#quantity').val();
		  var dataString = "product=" + product + "&size=" + size + "&quantity=" + quantity;
		  
		   $.ajax({
			type: "POST",
			url: "qdata.php",
			data: dataString,
			cache: false,
			success:function(html){
			
			$("#cost").val(html);	
			}
										 
		 });
			
		});
 
  $('#quantity').change(function(){
										 
		  var product = $('#paper').val();
		  var size = $('#size').val();
		  var quantity = $('#quantity').val();
		  var dataString = "product=" + product + "&size=" + size + "&quantity=" + quantity;
		  
		   $.ajax({
			type: "POST",
			url: "qdata.php",
			data: dataString,
			cache: false,
			success:function(html){
			
			$("#cost").val(html);	
			}
										 
		 });
			
		});
 
 
 
 
});