<script type="text/javascript" charset="utf-8">
  jQuery(document).ready(function($) {
 
  function zipToState(zip) {
    var states = ['0 500 state1',
                  '501 1000 state2',
                  '1001 1500 state3',
                  '75502 75502 state4'
                 ];
 
    for(var i=0;i<states.length;i++) {
       var d = states[i].split(' ');
          if (zip>=d[0] && zip<=d[1]) return d[2];
     } 
}
 
var zipcode = '{INSERTANS:54579x4x40}'; // numeric field
alert (zipcode);
var state = zipToState(zipcode);
alert(state);
document.getElementById('answer54579x4x127').value= state; // text field
}); 
</script>