Given :
- Height of cylinder, h = 20 inches
- Radius of cylinder, r = 7 inches
To Find :
- Surface area of cylinder = ?
Solution :
As, we have :
- Height of cylinder, h = 20 inches
- Radius of cylinder, r = 7 inches
To find surface area, we have a formula :
[tex] \Large \underline{\boxed{\tt{Surface \: Area = 2\pi rh+2 \pi r^{2}}}}[/tex]
By filling values :
[tex] \sf : \implies Surface \: Area = 2 \pi (7)(20)+2 \pi (7)^{2}[/tex]
[tex] \sf : \implies Surface \: Area = 280 \pi + 2 \pi (7)(7)[/tex]
[tex] \sf : \implies Surface \: Area = 280 \pi + 98 \pi[/tex]
Now, put value of π = 22/7
[tex] \sf : \implies Surface \: Area = 280\times \dfrac{22}{7} + \cancel{98} \times \dfrac{22}{\cancel{7}}[/tex]
[tex] \sf : \implies Surface \: Area = 40 \times 22 + 14 \times 22[/tex]
[tex] \sf : \implies Surface \: Area = 40 \times 22 + 14 \times 22[/tex]
[tex] \sf : \implies Surface \: Area = 880 + 308[/tex]
[tex] \sf : \implies Surface \: Area = 1188[/tex]
[tex] \Large \underline{\boxed{\tt{Surface \: Area = 1188 \: inches^{2} }}}[/tex]
Hence, Surface area of given cylinder is 1188 inches².
