8 * 3 = 24
8 * 5 = 40
3 * 5 = 15
Therefore, the surface area of the cuboid is 2(24 + 40 + 15) = 158.
ANSWER
[tex]158c {m}^{2} [/tex]
EXPLANATION
The total surface area of a rectangular prism is
[tex] = 2(lw + lh + wh)[/tex]
The length is
[tex]l = 8cm[/tex]
The width is
[tex]w= 3cm[/tex]
The height is;
[tex]h = 5cm[/tex]
We substitute the values in to the formula;
[tex] = 2(8 \times 5 + 8 \times 3 + 3 \times 5)[/tex]
[tex] = 2(40 + 24 + 15)[/tex]
[tex] = 2 \times 79[/tex]
[tex] = 158c {m}^{2} [/tex]
