What is the surface area of this design?
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Answer:
256 in²
Step-by-step explanation:
There are numerous ways to find the total area of this figure. One of them is to add up the individual areas of the 8 surfaces.
Another is to add the areas of the 5" wide surfaces (their total length is 32 inches, the same as the perimeter of the L-shaped face), and the areas of the L-shaped surfaces (equivalent to an 8×12 rectangle when one is fit upside down on the other).
Using this second method, we get an area of ...
(5 in)×(32 in) + (8 in)×(12 in) = 160 in² +96 in² = 256 in²