Each of the cubes is 1 inch in length. The total surface area of the solid is inch2.
The left surfaces area is 6 inch2
The front surfaces area is 10 inch2
The top surfaces area is 3 × 4 = 12 inch2
The right surfaces area is 6 inch2
The back surfaces area is 10 inch2
The bottom surfaces area is 3 × 4 = 12 inch2
So, the total surfaces area is 6 + 10 + 12 + 6 + 10 + 12 = 56 inch2