Answer:
3 dolls
Explanation:
LOL this is a really logical question, if 2 dolls can balance 4 pencils and 3 pencils can balance 1 truck we will need 3 dolls i think because we can just say 2 pencil is a doll, so if there is 3 pencils that means there willl be more then 1 doll, but 2 dolls would be too light also bc thats only 2/3 of the weight but 3 dolls would do the trick even tho i still doubt it would be a lil too heavy