function updateTotal(theElement) {
	var theForm = theElement.form;
	len = theForm.length;
	total = 0;
	for(i=0; i<len; i++){
		if(theForm[i].type=="checkbox"){
			if(theForm[i].checked){
				if(isFinite(theForm[i].value)){
					total = total + Number(theForm[i].value);
				}
				
			}
		}
	}
	total = total.toFixed(2);
	theForm.total.value = total;
}