Puse solo la mitad de la harina en el bol.
I only put half the (quantity of) flour in the bowl.
Ella tiene el doble de hermanos que él.
She has twice as many siblings as he does.
Why is it de LA harina, but not de LOS hermanos? Is the definite article always skipped after doble de? There was a quiz question for "________ tiempo" meant to be filled with doble. Would it be "el doble de" or "el doble del"?