Hidden elements

HTML

<ul class="relatedelements">
   <li class="1 hidden">anything</li>
   <li class="2 hidden">anything</li>
   <li class="3 hidden">anything</li>
   <li class="4 hidden">anything</li>
    <li class="5">anything</li>
    <li class="6">anything</li>
    <li class="7 hidden">anything</li>
</ul>

<div class="num-relatedelements">

</div>

CSS

.hidden {
    display: none;
}

JavaScript

$(function() {  
   var numrelated= $('.relatedelements > li:not(.hidden)').length;
   alert(numrelated);
   $('.num-relatedelements').html(numrelated); 
});