Answer:
1042 square inches is the total surface area of composite solid.
Step-by-step explanation:
It is clear from the image that the resulting composite solid is a cuboid.
whose sides are as follows:
Across the length there are 3 blocks along the side of 7 inches each.
Length = [tex]7 \times 3 = 21\ inch[/tex]
Width = 5 inch
Across the height there are 4 blocks along the side of 4 inches each.
Height = [tex]4 \times 4 = 16\ inch[/tex]
We know that total surface area of a cuboid is as follows:
[tex]\text{Total Surface Area = } 2 (l\times w+ w \times h+ h \times l)[/tex]
[tex]\Rightarrow 2 (21 \times 5 + 16 \times 21 + 16 \times 5 )\\\Rightarrow 2 (105 + 336+80)\\\Rightarrow 2 \times 521\\\Rightarrow 1024[/tex]
Hence, total surface area = 1024 square inches
