//var $adult_price;
//var $child_price;

function init() {
	updatePrice();
	document.getElementById( "adults" ).onchange = selectOnChange;
	document.getElementById( "children" ).onchange = selectOnChange;
	}

function selectOnChange() {
	document.getElementById( "action_new" ).checked = true;
	updatePrice();
	}

function updatePrice() {
	var $adults = document.getElementById( "adults" ).value;
	var $children = document.getElementById( "children" ).value;

	if ( $adults != 0 || $children != 0 ) {
		document.getElementById( "cost" ).innerHTML = "Total Amount: $" + ( $adults*$adult_price + $children*$child_price );
		}
	else {
		document.getElementById( "cost" ).innerHTML = " ";
		}
	}

window.onload = init;