Question

How to implement following for the current .packages if I have multiple having .packages class?

$('.packages').each(function(){
    var sizeOfLi = $(".packages:last > li").width();
});

Answer 1

var sizeOfAllLi = $(".packages:last > li").map(function() {
  return $(this).width();
});

The map function iterates over the jQuery collection and calls the function provided in the argument, with this set to the current element. It will collect all the return values in an array a jQuery collection (see comments). If you want an array, add .get() to the end of the above.

Inside the function, need to re-wrap this as a jQuery element so we can use the jQuery’s .width(), since this is a bare DOM element.