[tex]723cm^2[/tex]
Explanation
Step 1
to find the area, imagine the unfolded cylindrical box
Let
length=18 cm
width=2*pi*radius
radius= 5 cm
[tex]\begin{gathered} \text{width}=2\cdot\pi\cdot5\text{ cm} \\ \text{width}=10\cdot\pi\cdot\text{cm} \\ \text{width}=31.4\text{ cm} \end{gathered}[/tex]
Step 2
now, the total area would be
[tex]\begin{gathered} \text{total area= area of the rectangle+twice area of the circle} \\ \text{replacing} \\ \text{total area=(length}\cdot widht9+2(\pi\cdot radius^2) \\ \text{total area=(18 cm}\cdot31.4\text{ cm)+2(3.14}\cdot25cm^2) \\ \text{total area=565.2 cm}^2+157.07cm^2 \\ \text{total area=722.27 cm}^2 \\ \text{rounded} \\ 723cm^2 \end{gathered}[/tex]
I hope this helps you
