I am wanting to look at two fields and verify that only one field has a value.  the code below is what I am using but it does not appear to work correctly.  

any ideas or suggestions would be greatly appreciated.  

//compare values for .miles and .gas
$(document).ready(function() {
  $('.Submit').hide();
  $('.miles input').on('blur change', function() {
    if($('.miles input').val() > $('.gas select').val()) || ($('.gas input').val() > $('.miles select').val(){
      $('.Submit').show();
    } else {
      $('.Submit').hide();
    }
  });
});

mileage == miles

Transportation == gas