Answer:
422 cm²
Step-by-step explanation:
Surface area of the composite figure = (surface area of the upper cuboid + surface area of lower cuboid) - 2(base area of the lower cuboid)
Surface area of composite figure = [tex] (2(lw + lh + hw)) + (2(lw + lh + hw)) - 2(l*w) [/tex]
Upper cuboid has the following dimensions:
[tex] l = 4, w = 3, h = 8 [/tex]
Lower cuboid has the following dimensions:
[tex] l = 10, w = 7, h = 5 [/tex]
Plug these values into the formula
Surface area of composite figure
[tex] = (2(4*3 + 4*8 + 8*3)) + (2(10*7 + 10*5 + 5*7)) - 2(4*3) [/tex]
[tex] = (2(12 + 32 + 24)) + (2(70 + 50 + 35)) - 2(12) [/tex]
[tex] = (136 + 310) - 24 [/tex]
[tex] = 446 - 24 = 422 [/tex]
Surface area of composite figure = 422 cm²
