$(document).ready(function(){
	$('select[name="loan_type"]').change(function(){
		var loan_type = ($('select[name="loan_type"]').val());
		var loan_length = ($('select[name="loan_length"]').val());
		if(loan_type == "used"){
			$('select[name="loan_length"] option[value="3"]').attr('disabled','disabled');
			$('select[name="loan_length"] option[value="4"]').attr('disabled','disabled');
			$('select[name="loan_length"] option[value="5"]').attr('disabled','disabled');
			$('select[name="loan_length"] option[value="1"]').attr('selected','selected');
		}
		if(loan_type == "new"){
			$('select[name="loan_length"] option[value="3"]').attr('disabled','');
			$('select[name="loan_length"] option[value="4"]').attr('disabled','');
			$('select[name="loan_length"] option[value="5"]').attr('disabled','');
		}		
	});
})