Answer:
The answer is 8
Explanation:
so first we have to figure out how much wool card cost for 1 ore card. 6 divided by 3 is 2. That means for 1 ore card Jillian needs to give David 2 wool cards so if you multiply 4 times 2 you get 8. The 4 is representing the ore cards and since Jillian is trying to get 4 ore cards she has to add 2 , 4 times. 2+2+2+2 gives you 8 (2 x 4)
I hoped that helped