Your answer would be 6 boxes.
Work:
We will need 3 for each, and there's 24 so we just multiply those two together: 24 x 3 = 72
If there is 12 in each box, and we need 72, we need to find out how many boxes we would need to have enough, even if there's leftovers: 72/12= 6.
So, we will need 6 boxes, and there will be none left over.
Hope I heled!
