Answer:
653
Explanation:
The surface area of the larger cube is
2(10 x 7) + 2(12x7) + 2(10x12) = 140 + 168 + 240 = 548
The surface area of the smaller cube (minus the surface that is covered by the other figure)
4(8x3) + 1(3x3) = 96 + 9 = 105
105 + 548 = 653