Answer: 20
Explanation:
The base square is 4 x 4, which is 16. That part is easy, but the other part needs more thinking.
We have two more visible full squares, which we can add on to our 16, putting it at 18. But that half squares, we have 4 total have squares. We know that 1/2 + 1/2 = 1
So, 1/2 + 1/2 + 1/2 + 1/2 = 2.
We eventually get 16 (original square) + 2 (two other full squares) + 2 (half squares) resutling in 20.