Hi, is it possible to have null values in a numeric fill in blank question?

Let me explain in more detail, I have several questions in which I provide to the user 4 fields, sometimes the user must answer in all the fields, but in others he must answer at 2 or 3 fields ( Remember that I add 4 fields, to distract the user, so it won't be as easy as it seems ).

Example:

Question 1: 23
Question 2:
Question 3:
Question 4: 55

My problem is that when I click the submit answer button, it won't score the question since it asks for all fields to be answered, as I stated before, some will be empty.

So my question, is it possible to have null values in the fields and this question object have no problem allowing them, so it could score them?

Thanks

Nulls aren't available at present so you need to find a workaround.
You have some dummy questions so why not ask the user to mark the dummy questions with 0 and the real questions with the answers.
Not ideal but the best thought that I can come up with at the moment.

Thanks for the answer Nick, that's what I thought in the weekend, I'll need to do specific instructions for the student so it can always put a 0 in those fields.

You could consider that it does add a further demonstration of understanding, it would depend on how the questions were written.