Respuesta :
[tex]\bf \textit{total surface area of a cylinder}\\\\
SA=2\pi r(h+r)~~
\begin{cases}
r=radius\\
h=height\\
-----\\
r=4\\
h=12
\end{cases}\implies SA=2\pi (4)(12+4)
\\\\\\
SA=8\pi (16)\implies SA=128\pi \\\\
-------------------------------\\\\
\textit{volume of a cylinder}\\\\
V=\pi r^2 h~~
\begin{cases}
r=radius\\
h=height\\
-----\\
r=4\\
h=12
\end{cases}\implies V=\pi (4)^2(12)\implies V=192\pi[/tex]
[tex]\bf -------------------------------\\\\ \cfrac{SA}{V}\qquad \qquad \cfrac{128\pi }{192\pi }\implies \stackrel{simplified}{\cfrac{2}{3}}[/tex]
[tex]\bf -------------------------------\\\\ \cfrac{SA}{V}\qquad \qquad \cfrac{128\pi }{192\pi }\implies \stackrel{simplified}{\cfrac{2}{3}}[/tex]
Answer:
Correct option is C.
Step-by-step explanation:
Given the radius and height of cylinder. we have to find out the ratio of surface area to the volume of the cylinder.
Radius=4 ft
Height=12 ft
[tex]\text{Surface Area of cylinder=}2\pi r(r+h)=2\pi 4(4+12)=128\pi ft^2[/tex]
[tex]\text{Volume of cylinder=}\pi r^2h=\pi (4^2)(12)=192\pi ft^2[/tex]
[tex]Ratio=\frac{Surface area}{volume}[/tex]
=[tex]\frac{128}{192}=0.67ft^2[/tex]
Hence, correct option is C.