похоже на зависимые селекты тоже можно ставить счётчик, как на открывашка.
jquery тут нафиг ненужна, но раз хочется ...
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title> - jsFiddle demo</title>
<script type='text/javascript' src='http://code.jquery.com/jquery-2.1.3.js'></script>
<script>
$(function() {
var d = {
count_adult: $("#count_child option"),
count_child: $("#count_adult option")
};
el = {
count_adult: $("#count_child")[0],
count_child: $("#count_adult")[0]
};
$("#count_adult, #count_child").change(function() {
var a = this.id,
e = 10 - this.value,
b = el[a],
v = b.value;
b.options.length = 0;
$.each(d[a], function(a, c) {
c.value <= e && b.options.add(c)
});
b.value = v;
}).change()
});</script>
</head>
<body>
<select class="form-control" id="count_adult" name="count_adult">
<option value="1" price="160">1 adult - 160 Points</option>
<option value="2" price="320">2 adults - 320 Points</option>
<option value="3" price="480">3 adults - 480 Points</option>
<option value="4" price="640">4 adults - 640 Points</option>
<option value="5" price="800">5 adults - 800 Points</option>
<option value="6" price="960">6 adults - 960 Points</option>
<option value="7" price="1120">7 adults - 1120 Points</option>
<option value="8" price="1280">8 adults - 1280 Points</option>
<option value="9" price="1440">9 adults - 1440 Points</option>
<option value="10" price="1600">10 adults - 1600 Points</option>
</select>
<select class="form-control" id="count_child" name="count_child">
<option value="0" price="0">0 child - 0 Points</option>
<option value="1" price="120">1 child - 120 Points</option>
<option value="2" price="240">2 children - 240 Points</option>
<option value="3" price="360">3 children - 360 Points</option>
<option value="4" price="480">4 children - 480 Points</option>
<option value="5" price="600">5 children - 600 Points</option>
<option value="6" price="720">6 children - 720 Points</option>
<option value="7" price="840">7 children - 840 Points</option>
<option value="8" price="960">8 children - 960 Points</option>
<option value="9" price="1080">9 children - 1080 Points</option>
<option value="10" price="1200">10 children - 1200 Points</option>
</select>
</body>
</html>