$(document).ready(function(){	
	if($(".calc_upd").length) {
		updatePrice();
		$("input.calc_upd").keyup(updatePrice)
		$("select.calc_upd").change(updatePrice)
	}
	
	function updatePrice(){
		price = parseInt($("#price").val());
		if(isNaN(price)) price = 0;
		pack = parseInt($("#pack").val());
		add_price = 0;
		month_pay = 0;
		pays_num = pack;
		if(pack == 3){
			add_price = price / 0.9;	add_price = add_price.toFixed(2)
			month_pay = add_price / 3;	month_pay = month_pay.toFixed(2);
		} else if(pack == 6){
			add_price = price / 0.8; 	add_price = add_price.toFixed(2)
			month_pay = add_price / 6; 	month_pay = month_pay.toFixed(2);
		} else if(pack == 10){
			add_price = price / 0.7; 	add_price = add_price.toFixed(2)
			month_pay = add_price / 10; month_pay = month_pay.toFixed(2);
		} 
		$("#add_price").html(add_price);
		$("#month_pay").html(month_pay);
		$("#pays_num").html(pays_num-1);
	}
	
});