OK, surely this must be your homework, so we can't just do it for you. First read this:
then invest two hours here so you can do what you asked (which is a very, very basic thing):
After that you'll be able to do it yourself and won't get into trouble for turning in our solution as your own.
Next the count of numbers less than 4 is a scalar (6), so what do you mean by "add those quantity"? What quantity? It's a single number 6 so there is nothing to add to it. Do you want to sum all the values less than 4?
