title: display elements if the last number in their id is smaller than i
body: <p>I have span elements that are named id="tag1", id="tag2", etc. and I only want to <code>.show()</code> the spans with a last number in their id smaller than eg. 19.<br>
  These elements belong to a <code>class="notVis"</code>, which is <code>$(".notVis").hide();</code> when the page is first loaded.  </p>
  
  <p>I am entirely new at this and self-teaching, this is why the below attempted code will produce a lot of laughs, I am sure. Thanks for any help!</p>
  
  <pre><code>var iMax = 19;
  var i = 3;
  var field = "tag" + i;
  while(i &lt; iMax){
     $("#field").show(); i = i + 1; field = "tag" + i;
  }
  </code></pre>