Can .animate be dynamic?

Can .animate be dynamic?

Im currently using a sliding menu using jquery. The tutorial can be found here (http://www.ilovecolors.com.ar/jquery-sliding-menu/ ). My question refers to a specific portion of the code. 

 
  1. $(this).animate({ width: "185px" }, {queue:false, duration:"normal"} );
Can the width be dynamic? Like can a variable be put in there? or does it have to be a set number? I ask this because the text i have with in the spans are different lengths, i had to make it animate out wider to make enough room for the longest span but then the shorter ones have a gap. I tried tinkering at this for hours and even tried .slide, but couldn't get the results i was looking for. Any help much appreciated.

Thanks,

Bryant