Answer:
40
Explanation:
So square A has a side of 4, therefore its area is 16 because you square the side length.
Square B has a side of 2 times Square A's side. So Square B has sidelength 8 as 4*2 = 8.
If Square B has side length 8, it has an area of 64.
The average is found by adding the two area and then dividing by 2. So,
64 + 16 = 80
80/2 = 40